SHORT-ACTING BENZODIAZEPINE SALTS AND THEIR POLYMORPHIC FORMS

Abstract

The invention relates to besylate salts of the compound of formula (I): Methods of preparing the salts, and their use as medicaments, in particular for sedative or hypnotic, anxiolytic, muscle relaxant, or anticonvulsant purposes is also described.

Description

This invention relates to salts of a short acting benzodiazepine, and to use of the salts as medicaments, in particular for sedative or hypnotic, anxiolytic, muscle relaxant, or anticonvulsant purposes.

European Patent No. 1,183,243 describes short-acting benzodiazepines that include a carboxylic acid ester moiety and are inactivated by non-specific tissue esterases. An organ-independent elimination mechanism is predicted to be characteristic of these benzodiazepines, providing a more predictable and reproducible pharmacodynamic profile. The compounds are suitable for therapeutic purposes, including sedative-hypnotic, anxiolytic, muscle relaxant and anticonvulsant purposes. The compounds are short-acting CNS depressants that are useful to be administered intravenously in the following clinical settings: preoperative sedation, anxiolysis, and amnestic use for perioperative events; conscious sedation during short diagnostic, operative or endoscopic procedures; as a component for the induction and maintenance of general anesthesia, prior and/or concomitant to the administration of other anaesthetic or analgesic agents; ICU sedation.

One of the compounds disclosed in EP 1,183,243 (in Example Ic-8, page 36) is Methyl 3-[(4S)-8-bromo-1-methyl-6-(2-pyridinyl)-4H-imidazol [1,2-a][1,4]benzodiazepin-4-yl]propanoate, as shown in formula (I) below:

Whilst the free base of formula (I) is stable when stored at 5° C., samples stored at 40° C./75% relative humidity (open) are observed to deliquesce, become yellow to orange in colour, and show notable decreases in content relative to initial (see Example 1 below).

It has now surprisingly been found that the compound of formula (I) forms highly crystalline mono (benzenesulphonic acid) besylate salts that are easily isolated from a range of pharmaceutically acceptable solvents and show good thermal stability, low hygroscopicity and high aqueous solubility.

According to the invention there is provided a besylate salt of a compound of formula (I). Preferably the salt is a crystalline salt. Preferably the crystalline salt has a stoichiometry of 1:1 compound of formula (I):besylate. Preparation and characterisation of polymorphic forms of besylate salts is described in the Examples below.

According to the invention there is provided a crystalline polymorph of a besylate salt of a compound of formula (I) (herein designated besylate Form 1), that exhibits an X-ray powder diffraction (XRPD) pattern which comprises a characteristic peak at about 7.3, 7.8, 9.4, 12.1, 14.1, 14.4, 14.7, or 15.6 degrees two-theta.

Preferably the besylate Form 1 crystalline polymorph exhibits an XRPD pattern which comprises characteristic peaks at about 7.3, 7.8, 9.4, 12.1, 14.1, 14.4, 14.7, and 15.6 degrees two-theta.

More preferably the besylate Form 1 crystalline polymorph exhibits an XRPD pattern which comprises characteristic peaks at: 7.25 (10.60), 7.84 (72.60), 9.36 (12.10), 12.13 (32.50), 14.06 (48.50), 14.41 (74.30), 14.70 (50.70), 15.60 (26.90) [angle two-theta degrees (percentage relative intensity)].

Preferably the besylate Form 1 crystalline polymorph has a differential scanning calorimetry (DSC) onset melting temperature in the range 187-204° C., preferably about 191-192° C.

A crystal structure of Form 1 has been resolved at 190K (R factor of 6.3). Form I has a stoichiometry of 1:1 compound:besylate. Its crystallographic asymmetric unit contains two independent compound molecules and two besylate molecules. The two independent compound molecules are singly protonated on the imidazole ring. The crystal structure has unit cell dimensions of a=7.6868 Å, b=29.2607 Å, c=12.3756 Å, α=90°, β=97.7880°, γ=90°, and a space group of P2₁. The crystal structure is described in more detail in Example 9, and crystallographic coordinates are given in Table 17. Bond lengths and angles for Form 1 are given in Tables 19 and 20, respectively.

According to the invention there is provided a besylate salt of a compound of formula (I) which is a crystalline polymorph comprising a crystal with unit cell dimensions of a=7.6868 Å, b=29.2607 Å, c=12.3756 Å, α=90°, β=97.7880°, γ=90°.

There is also provided according to the invention a besylate salt of a compound of formula (I) which is a crystalline polymorph having a crystal structure defined by the structural coordinates as shown in Table 17.

There is further provided according to the invention a besylate salt of a compound of formula (I) with bond lengths and angles as shown in Tables 19 and 20, respectively.

There is further provided according to the invention a crystalline polymorph of a besylate salt of a compound of formula (I) (herein designated besylate Form 2), that exhibits an XRPD pattern which comprises a characteristic peak at about 8.6, 10.5, 12.0, 13.1, 14.4, or 15.9 degrees two-theta.

Preferably the besylate Form 2 crystalline polymorph exhibits an XRPD pattern which comprises characteristic peaks at about 8.6, 10.5, 12.0, 13.1, 14.4, and 15.9 degrees two-theta.

More preferably the besylate Form 2 crystalline polymorph exhibits an XRPD pattern which comprises characteristic peaks at: 8.64 (17.60), 10.46 (21.00), 12.03 (22.80), 13.14 (27.70), 14.42 (11.20), 15.91 (100.00) [angle two-theta degrees (percentage relative intensity)].

Preferably the besylate Form 2 crystalline polymorph has a differential scanning calorimetry (DSC) onset melting temperature in the range 170-200° C., preferably about 180° C.

A crystal structure of Form 2 has been resolved at 190K (R factor of 3.8). Form 2 has stoichiometry of 1:1 compound:besylate. Its crystallographic asymmetric unit contains one compound molecule and one besylate molecule. The compound molecule is singly protonated on the imidazole ring. The crystal structure has unit cell dimensions of a=8.92130 Å, b=11.1536 Å, c=25.8345 Å, α=90°, β=90°, γ=90°, and a space group of P2₁2₁2₁. The crystal structure is described in more detail in Example 10, and crystallographic coordinates are given in Table 18. Bond lengths and angles for Form 2 are given in Tables 21 and 22, respectively.

According to the invention there is provided a besylate salt of a compound of formula (I) which is a crystalline polymorph comprising a crystal with unit cell dimensions of a=8.92130 Å, b=11.1536 Å, c=25.8345 Å, α=90°, β=90°, γ=90°.

There is also provided according to the invention a besylate salt of a compound of formula (I) which is a crystalline polymorph having a crystal structure defined by the structural coordinates as shown in Table 18.

There is further provided according to the invention a besylate salt of a compound of formula (I) with bond lengths and angles as shown in Tables 21 and 22, respectively.

There is further provided according to the invention a crystalline polymorph of a besylate salt of a compound of formula (I) (herein designated besylate Form 3), that exhibits an X-ray powder diffraction (XRPD) pattern which comprises a characteristic peak at about 7.6, 11.2, 12.4, 14.6, 15.2, 16.4, or 17.7 degrees two-theta.

Preferably the besylate Form 3 crystalline polymorph exhibits an XRPD pattern which comprises characteristic peaks at about: 7.6, 11.2, 12.4, 14.6, 15.2, 16.4, and 17.7 degrees two-theta.

More preferably the besylate Form 3 crystalline polymorph exhibits an XRPD pattern which comprises characteristic peaks at: 7.61 (65.70), 11.19 (33.20), 12.38 (48.70), 14.63 (30.60), 15.18 (33.20), 16.40 (29.60), 17.68 (51.30) [angle 2θ° (percentage relative intensity)].

Preferably the besylate Form 3 crystalline polymorph has a differential scanning calorimetry (DSC) onset melting temperature in the range 195-205° C., preferably about 200-201° C.

There is further provided according to the invention a crystalline polymorph of a besylate salt of a compound of formula (I) (herein designated besylate Form 4), that exhibits an XRPD pattern which comprises a characteristic peak at about 7.6, 10.8, 15.2, 15.9, or 22.0 degrees two-theta.

Preferably the besylate Form 4 crystalline polymorph exhibits an XRPD pattern which comprises characteristic peaks at about: 7.6, 10.8, 15.2, 15.9, and 22.0 degrees two-theta.

Preferably the besylate Form 4 crystalline polymorph exhibits an XRPD pattern which comprises characteristic peaks at: 7.62 (83.50), 10.75 (14.70), 15.17 (37.80), 15.85 (28.70), 22.03 (100) [angle 2θ° (percentage relative intensity)].

Preferably the besylate Form 4 crystalline polymorph has a differential scanning calorimetry (DSC) onset melting temperature in the range 180-185° C., preferably about 182° C.

A preferred salt is the besylate Form 1 based on the robustness of formation, yield, purity and chemical and solid form stability.

There is also provided according to the invention a method of making a besylate salt of a compound of formula (I), which comprises reacting a free base of a compound of formula (I) with benzene sulphonic acid.

Also according to the invention there is provided a method of making a salt of the invention, which comprises contacting a free base of a compound of formula (I) with benzene sulphonic acid in solution to cause formation of a precipitate of the besylate salt. Preferably the method further comprises isolating the precipitate.

Preferably the free base is dissolved in toluene, ethanol, ethyl acetate, MtBE, dichloromethane (DCM), isopropyl acetate, ethyl formate, methanol, or acetone. More preferably the free base is dissolved in toluene or ethyl acetate. Preferably the benzene sulphonic acid is dissolved in ethanol.

The besylate Form 1 may be prepared by contacting a solution of a free base of a compound of formula (I) in toluene, ethyl acetate, acetone, isopropyl acetate, or ethyl formate with a solution of benzene sulphonic acid in ethanol to cause formation of a precipitate of the salt.

There is also provided according to the invention a besylate salt of a compound of formula (I) which is obtainable by the above method.

The besylate Form 2 may be prepared by contacting a solution of a free base of a compound of formula (I) in methanol with a solution of benzene sulphonic acid in ethanol to cause formation of a precipitate of the salt. Preferably the mixture is cooled below ambient temperature (for example 4° C.).

There is also provided according to the invention a besylate salt of a compound of formula (I) which is obtainable by the above method.

The besylate Form 3 may be prepared by seeding liquor resulting from crystallisation of Form 1 from ethyl acetate/ethanol with Form 1. Preferably the liquor is cooled below ambient temperature (for example 4° C.).

In one embodiment the besylate Form 3 may be prepared by seeding, with a besylate Form 1 crystalline salt of a compound of formula (I), a filtrate solution separated from the precipitate formed by contacting a solution of a compound of formula (I) in ethyl acetate with a solution of benzene sulphonic acid in ethanol, to produce the besylate Form 3 crystalline polymorph.

There is also provided according to the invention a besylate salt of a compound of formula (I) which is obtainable by any of the above methods.

The besylate Form 4 may be prepared by re-crystallising besylate Form 1 from isopropyl acetate/ethanol, preferably 40% isopropyl acetate/ethanol.

There is also provided according to the invention a besylate salt of a compound of formula (I) which is obtainable by the above method.

Salts of the invention may also be prepared by crystallising compound of formula (I) besylate from a suitable solvent, or from a suitable solvent/anti-solvent or solvent/co-solvent mixture. The solution or mixture may be cooled and/or evaporated to achieve crystallisation if appropriate.

We have found that crystallisation of Form 2 is observed in conditions where there are extremes of either polarity (for example acetonitrile:water) or lipophilicity (n-nonane), or both (dimethyl sulphoxide:1,2-dichlorobenzene).

Examples of solvents for crystallisation of Form 2 are: nonane; methanol.

Examples of solvent/anti-solvent mixtures for crystallisation of Form 1 are: dimethylacetamide/methyl isobutyl ketone; dimethylacetamide/tetrachloroethylene; acetonitrile/3-methylbutan-1-ol; acetonitrile/1,2-dichlorobenzene; acetonitrile/pentylacetate; methanol/3-methylbutan-1-ol; methanol/methyl isobutyl ketone; 2,2,2-trifluoroethanol/1,4-dimethylbenzene; ethanol/methyl isobutyl ketone; ethanol/1,4-dimethylbenzene; propan-1-ol/1,2-dichlorobenzene; propan-1-ol/tetrachloroethylene; propan-2-ol/1,2-dichlorobenzene; propan-2-ol/n-nonane; 2-methoxy ethanol/water; 2-methoxy ethanol/pentyl acetate; 2-methoxy ethanol/1,4-dimethylbenzene; tetrahydrofuran/water; tetrahydrofuran/3-methylbutan-1-ol; tetrahydrofuran/1,2-dichlorobenzene; tetrahydrofuran/ethyl acetate; tetrahydrofuran/1,3-dimethylbenzene.

Examples of solvent/anti-solvent mixtures for crystallisation of Form 2 are: ethanol/ethyl acetate; ethanol/methyl isobutyl ketone; ethanol/p-cymene; dimethylsulfoxide/1,2-dichlorobenzene; acetonitrile/water; ethano/1,2-dichlorobenzene; ethanol/tetrachloroethylene; tetrahydrofuran/1,2-dichlorobenzene; tetrahydrofuran/ethyl acetate.

According to a preferred embodiment, Form 1 is crystallised from 2-methoxyethanol/pentyl acetate.

According to a preferred embodiment, Form 2 is crystallised from ethanol/ethyl acetate.

According to a preferred embodiment, Form 2 is crystallised from methanol/ethanol (preferably by cooling a solution of compound of formula (I) besylate in methanol/ethanol below ambient temperature, for example 4° C.).

According to a preferred embodiment, Form 3 is crystallised from ethanol/ethyl acetate (suitably by cooling the mixture below ambient temperature, for example 4° C.).

According to a preferred embodiment, Form 4 is crystallised from isopropyl acetate/ethanol (preferably by cooling a solution of compound of formula (I) besylate in isopropyl acetate/ethanol to ambient temperature).

There is also provided according to the invention a besylate salt of a compound of formula (I) obtainable by any of the above methods.

Methods of preparing salts of the invention are described in detail in the Examples below.

A salt of the invention may be used as a medicament, in particular for sedative or hypnotic, anxiolytic, muscle relaxant, or anticonvulsant purposes.

While it is possible for a salt of the invention to be administered as a bulk active chemical, it is preferably provided with a pharmaceutically acceptable carrier, excipient, or diluent in the form a pharmaceutical composition. The carrier, excipient, or diluent must, of course, be acceptable in the sense of being compatible with the other ingredients of the composition and must not be deleterious to the recipient.

Accordingly, the present invention provides a pharmaceutical composition comprising a salt of the invention and a pharmaceutically acceptable carrier, excipient, or diluent.

Pharmaceutical compositions of the invention include those suitable for oral, rectal, topical, buccal (e.g. sub-lingual) and parenteral (e.g. subcutaneous, intramuscular, intradermal or intravenous) administration.

Preferably a salt of the invention is provided in the form of a pharmaceutical composition for parenteral administration, for example, by intravenous or intramuscular injection of a solution. Where the pharmaceutical composition is for parenteral administration, the composition may be an aqueous or non-aqueous solution or a mixture of liquids, which may include bacteriostatic agents, antioxidants, buffers or other pharmaceutically acceptable additives.

A preferred formulation of a salt of the invention is in an aqueous acidic medium of pH 2-4 or in an aqueous solution of a cyclodextrin (CD). Cyclodextrins that can be used for these formulations are either the anionically charged sulfobutylether (SBE) derivatives of β-CD, specifically SBE7-β-CD, marketed under the tradename Captisol by CyDex, Inc. (Critical Reviews in Therapeutic Drug Carrier Systems, 14 (1), 1-104 (1997)), or the hydroxypropyl CD's.

A further preferred formulation of a salt of the invention is a lyophilised formulation comprising, in addition to the salt, at least one of the following agents: ascorbic acid, citric acid, maleic acid, phosphoric acid, glycine, glycine hydrochloride, succinic acid or tartaric acid. These agents are believed to be useful as buffering, caking or vizualisation agents. In some cases it may be beneficial to include sodium chloride, mannitol, polyvinylpyrrolidone, or other ingredients in the formulation.

The preferred method of formulation (i.e., acid buffer or CD-based) may depend on the physicochemical properties (e.g., aqueous solubility, pKa, etc.) of a particular salt. Alternatively the salt may be presented as a lyophilized solid for reconstitution with water (for injection) or a dextrose or saline solution. Such formulations are normally presented in unit dosage forms such as ampoules or disposable injection devices. They may also be presented in multi-dose forms such as a bottle from which the appropriate dose may be withdrawn. All such formulations should be sterile.

According to the invention there is provided a method for producing sedation or hypnosis in a subject, which comprises administering an effective sedative or hypnotic amount of a salt of the invention to the subject.

There is also provided according to the invention a method for inducing anxiolysis in a subject, which comprises administering an effective anxiolytic amount of a salt of the invention to the subject.

There is further provided according to the invention a method for inducing muscle relaxation in a subject, which comprises administering an effective muscle relaxant amount of a salt of the invention to the subject.

There is further provided according to the invention a method for treating convulsions in a subject, which comprises administering an effective anticonvulsant amount of a salt of the invention to the subject.

According to the invention there is also provided use of a sedative or hypnotic amount of a salt of the invention in the manufacture of a medicament for producing sedation or hypnosis in a subject.

According to the invention there is also provided a salt of the invention for producing sedation or hypnosis in a subject.

There is also provided according to the invention use of an anxiolytic amount of a salt of the invention in the manufacture of a medicament for producing anxiolysis in a subject.

There is also provided according to the invention a salt of the invention for producing anxiolysis in a subject.

There is further provided according to the invention use of a muscle relaxant amount of a salt of the invention in the manufacture of a medicament for producing muscle relaxation in a subject.

There is further provided according to the invention a salt of the invention for producing muscle relaxation in a subject.

There is further provided according to the invention use of an anticonvulsant amount of a salt of the invention in the manufacture of a medicament for treating convulsions in a subject.

There is further provided according to the invention a salt of the invention for treating convulsions in a subject.

The subject is suitably a mammal, preferably a human.

A suitable pharmaceutical parenteral preparation for administration to humans will preferably contain 0.1 to 20 mg/ml of a salt of the invention in solution or multiples thereof for multi-dose vials.

Intravenous administration can take the form of bolus injection or, more appropriately, continuous infusion. The dosage for each subject may vary, however, a suitable intravenous amount or dosage of a salt of the invention to obtain sedation or hypnosis in a mammal would be 0.01 to 5.0 mg/kg of body weight, and more particularly, 0.02 to 0.5 mg/kg of body weight, the above being based on the weight of the salt which is the active ingredient. A suitable intravenous amount or dosage of a salt of the invention to obtain anxiolysis in a mammal would be 0.01 to 5.0 mg/kg of body weight, and more particularly, 0.02 to 0.5 mg/kg of body weight, the above being based on the weight of the salt which is the active ingredient. A suitable intravenous amount or dosage of a salt of the invention to obtain muscle relaxation in a mammal would be 0.01 to 5.0 mg/kg of body weight, and more particularly, 0.02 to 0.5 mg/kg of body weight, the above being based on the weight of the salt which is the active ingredient. A suitable intravenous amount or dosage of a salt of the invention to treat convulsions in a mammal would be 0.01 to 5.0 mg/kg of body weight, and more particularly, 0.02 to 0.5 mg/kg of body weight, the above being based on the weight of the salt which is the active ingredient.

Salts of the invention are short-acting CNS depressants that are useful to be administered intravenously in the following clinical settings: preoperative sedation, anxiolysis, and amnestic use for perioperative events; conscious sedation during short diagnostic, operative or endoscopic procedures; as a component for the induction and maintenance of general anaesthesia, prior and/or concomitant to the administration of other anaesthetic or analgesic agents; ICU sedation.

Preferred embodiments of the invention are described in the following Examples with reference to the accompanying drawings in which:

FIG. 1 shows a graph of compound of formula (I) content (% relative to initial) vs storage temperature;

FIG. 2 shows Differential Scanning Calorimetry (DSC) of LJC-039-081-1;

FIG. 3 shows DSC of LJC-039-081-1 (solid) overlayed with LJC-039-081-2 (dotted);

FIG. 4 shows DSC of besylate forms (Form1 solid, Form 2 dashed);

FIG. 5 shows DSC of besylate forms (Form1 solid, Form 3 dotted and dashed);

FIG. 6 shows chromatographs of LJC-039-037-1 at T⁰ and T⁴ (and relate to the results in Table 10);

FIG. 7 shows XRPD comparing LJC-039-037-1 (besylate salt) pre and post 4 week stability study;

FIG. 8A shows an XRPD comparison of besylate Form 1 and 2;

FIG. 8B shows Differential Scanning Calorimetry (DSC) overlays of Form 1 and 2;

FIG. 9A shows an XRPD comparison of besylate Form 1 and 3, and FIG. 9B shows overlays of Form 1 and 3;

FIG. 10 shows DSC of LJC-039-086-1 (besylate Form 4);

FIG. 11 shows results for besylate Form 1: A) XRPD for 100 mg batch LJC-039-037-1; B) DSC for 100 mg batch LJC-039-037-1; C) TGA for 100 mg batch LJC-039-037-1; D) ¹H NMR for 100 mg batch LJC-039-037-1; E) GVS for 100 mg batch LJC-039-037-1; F) XRPD post GVS for 100 mg batch LJC-039-037-1; G) XRPD post stability at 40° C./75% RH for 100 mg batch LJC-039-037-1; H) VT XRPD for 100 mg batch LJC-039-037-1; l) light polarised microscopy for 100 mg batch LJC-039-037-1;

FIG. 12 shows results for besylate Form 2: A) XRPD for 100 mg batch LJC-039-067-8; B) DSC for 100 mg batch LJC-039-067-8; C) DSC with ramp rate of 2° C./min; D) ¹H NMR for LJC-039-067-8;

FIG. 13 shows results for besylate Form 3: A) XRPD for LJC-039-081-2 (2^nd crop from liquors of LJC-039-081-1); B) DSC for LJC-039-081-2; C) DSC for LJC-039-081-2 (2° C./min ramp rate); D) TGA for LJC-039-081-2; E) ¹H NMR for LJC-039-081-2; F) GVS for LJC-039-081-2; G) XRPD post GVS for LJC-039-081-2;

FIG. 14 shows results for besylate Form 4: A) XRPD for LJC-039-086-1; B) DSC for LJC-039-086-1; C) ¹H NMR for LJC-039-086-1;

FIG. 15 shows HPLC chromatographs for release batch of besylate salts followed by Agilent ChemStation reports detailing results;

FIG. 16 shows chiral chromatography for LJC-039-081-1, and LJC-039-083-1;

FIG. 17 shows exemplar images (ca. 4-8 mm diameter field of view) of the solid forms observed in crystallisations of compound of formula (I) besylate;

FIG. 18 shows content of the asymmetric unit in Form 1;

FIG. 19 shows molecular structure as determined by single-crystal X-ray diffraction of a crystal of compound of formula (I) besylate, Form 1, grown from a 2-methoxyethanol:pentyl acetate solution with atoms represented by thermal ellipsoids. Only Hydrogens specifically located in the crystal structure are depicted;

FIG. 20 shows conformation adopted by the two independent molecules in Form 1;

FIG. 21 shows comparison of the conformation adopted by one independent molecule in Form 1 (top) and the conformation in Form 2 (bottom);

FIG. 22 shows comparison of the conformation adopted by the two independent besylates in Form 1, view along two different directions;

FIG. 23 shows comparison of the conformation adopted by one independent besylate in Form 1 (top) and the conformation in Form 2 (bottom);

FIG. 24 shows crystal structure, determined by single-crystal X-ray diffraction of a crystal of compound of formula (I) besylate grown from 2-methoxyethanol:pentyl acetate solution, viewed along the crystallographic a axis (a), b axis (b), and c axis (c);

FIG. 25 shows short contact C—O<3.6 Å, C—C<3.6 Å, and N—O<3.5 Å for Form 1;

FIG. 26 shows calculated powder pattern diffraction from single crystal X-ray diffraction data for Form 1;

FIG. 27 shows plate form crystals observed for compound of formula (I) besylate Form 2;

FIG. 28 shows content of the asymmetric unit in Form 2;

FIG. 29 shows molecular structure as determined by single-crystal X-ray diffraction of a crystal of compound of formula (I) besylate Form 2 with atoms represented by thermal ellipsoids. Only Hydrogens specifically located in the crystal structure are depicted;

FIG. 30 shows conformation adopted by the independent molecule in Form 2;

FIG. 31 shows conformation adopted by the independent besylate in Form 2, viewed along two different directions;

FIG. 32 shows crystal structure, determined by single-crystal X-ray diffraction of a crystal of compound of formula (I) besylate Form 2, viewed along the crystallographic a axis (a), b axis (b), and c axis (c);

FIG. 33 shows short contact C—O<3.6 Å, C—C<3.6 Å and N—O<3.5 Å for Form 2.;

FIG. 34 shows calculated powder pattern diffraction from single crystal X-ray diffraction data for Form 2;

FIG. 35 shows labelling of atomic centres for Compound of formula (I) besylate Form 1; and

FIG. 36 shows labelling of atomic centres for Compound of formula (I) besylate Form 2.

EXAMPLE 1

Solid-state Stability Study of Compound of Formula (I)

Method/Technique. 2 mg samples of compound of formula (I), accurately weighed, were placed in 4-mL clear glass screw-cap vials. Samples were tested at initial and after 34 days stored at 5° C./Ambient Relative Humidity (AMRH) Closed, 30° C./60% RH Closed, 40° C./75% RH Open and 60° C./AMRH Closed.

Samples were inspected visually for appearance. Compound of formula (I) content values were determined by the HPLC method in Table 1. The % weight/weight (% w/w) values were measured relative to standard samples of compound of formula (I) Batch U12438/79/1. The % area values were obtained by dividing the compound of formula (I) peak area by the total peak area.

TABLE 1
HPLC Method Condition
Column:
Phase =	Phenomenex Luna C18(2)
Length × i.d =	100 × 4.6 mm
Particle size =	3 μm
Mobile phase:	A = 1000:1 Water/Trifluoroacetic Acid
	B = 1000:0.5 Acetonitrile/Trifluoroacetic
	Acid
Flow rate:	1.0 mL/min
Column Temperature:	40° C.
Gradient	Time (min)	% A	% B
	0.0	80	20
	20.0	20	60
	25.0	20	60
	25.1	80	20
	30.0	80	20
Detection Wavelength:	230 mm
Sample Mass Injected	μg, typically 1 μL injection of
	1.0 mg compound of formula (I)/mL in
	60:40 Water/Acetonitrile
Retention Times	Compound of formula (I) elutes at
	approximately 7.64 min

Results

Appearance. Table 2 lists the appearance results.

TABLE 2
Summary of Compound of Formula (I) Appearance Data
Storage Condition	Timepoint days	Appearance
RT	initial	Cream to light yellow powder
5 C./AMRH Closed	34	Cream to light yellow powder
30 C./60% RH Closed	34	Cream to light yellow powder
40 C./75% RH Open	34	Deliquesced yellow mass on
		bottom of vial
60 C./AMRH Closed	34	Deliquesced dark yellow to
		orange mass on bottom of vial

Compound of Formula (I) Content (% w/w). The % w/w content values (see Table 3) show too much variability to detect differences between the initial value and those measured after 34 days at 5° C./AMRH Closed, 30° C./60% RH Closed or 40° C./75% RH Open. The average % w/w measured for the samples stored 34 days at 60° C./AMRH Closed show a 10% w/w decrease from the initial value.

Compound of Formula (I) Content (% area). The compound of formula (I) % area content (see Table 3 and FIG. 1) shows no significant change after 34 days stored at 5° C./AMRH Closed, but decreases steadily with increasing storage temperature for samples at 30° C./60% RH Closed, 40° C./75% RH Open or 60° C./AMRH Closed. Major degradation peaks are observed at RRT 0.68, 0.87 and RRT 0.90, but the chromatograms, which are relatively complex even at initial (23 peaks), also show many new small degradant peaks (e.g 7 peaks at 30° C./60% RH Closed; 13-20 peaks at 60° C./AMRH Closed). These observations suggest multiple degradation pathways. The degradent at RRT 0.68 is tentatively identified as the ester hydrolysis product (the free acid of compound of formula (I)). It is most prevalent in the 40° C./75% RH Open samples, as would be expected for a hydrolysis product.

TABLE 3
Summary of Compound of Formula (I) HPLC Data
		Compound of Formula	% Relative to
	Timepoint	(I) Content	Avg. Initial %
Storage Condition	Days	% w/w	% area	area
RT	initial	100.5	95.14	Avg = 94.81
RT	initial	104.1	94.47
5 C./AMRH Closed#11	34	102.6	95.30	100.52
30 C./60% RH Closed #11	34	94.7	94.20	99.36
40 C./75% RH Open #1	34	105.4	93.45	98.57
40 C./75% RH Open #2	34	100.3	93.39	98.50
60 C./AMRH Closed #1	34	93.4	87.77	92.57
60 C./AMRH Closed #2	34	91.1	87.77	92.57
Notes
1Only one sample was tested due to an autosampler sequencer error.

Conclusions

Compound of formula (I) is stable with respect to appearance and content for at least 34 days stored at 5° C./AMRH Closed. No change in appearance was noted at 30° C./60% RH Closed, but an approximately 0.6% drop in compound of formula (I) content relative to the initial % area was observed. Samples stored at 40° C./75% RH Open or 60° C./AMRH Closed deliquesced, became yellow to orange in colour and showed notable decreases (1.5 to 8%) in compound of formula (I) content relative to initial. Major degradation peaks at RRT 0.68, 0.87 and RRT 0.90 are observed along with numerous smaller peaks, suggesting multiple degradation pathways. The degradant at RRT 0.68 is tentatively identified as the ester hydrolysis product. These results indicate that compound of formula (I) should be stored refrigerated for long term storage.

EXAMPLE 2

The solubility of the compound of formula (I) was determined in a wide range of organic solvents. The solubility data is shown in Table 4 below.

TABLE 4
Solvent         Min solvent required/mg/ml
Methanol        446
Ethanol         324
Propan-2-ol     454
Acetone         214
Toluene         460
Ethyl acetate   218
Tetrahydrofuran 311
Acetonitrile    362

The data clearly shows that the compound of formula (I) has high solubility in common organic solvents. The preferred solvents are ethanol and toluene.

Two basic centres of the free base of the compound were measured for pKa. However, the basic centre of the pyridine ring had a pKa of 1.99. The pKa of the basic centre of the imidazole ring was measured to be 4.53.

Benzene sulphonic acid was used to produce a besylate salt of the compound of formula (I). Experiments were conducted on a 20 mg scale using 6 volumes of solvent. All reactions were carried out at ambient temperature with acids charged as stock solutions in ethanol (1M) or as solids depending on solubility.

Solids isolated showed significant peak shifts in ¹H NMR to confirm salt formation. X-Ray Powder Diffraction (XRPD) showed that the salt had crystalline indication. Table 5 summarises the isolated salt form.

TABLE 5
Entry	Salt	Solvent	ID
1	besylate	toluene	LJC-039-009-7

The salt was subsequently stored at 40° C./75% RH for two weeks then re-analysed by XRPD and HPLC for chemical purity to assess stability of the materials. The salt retained the same powder pattern after exposure to the humidity conditions, and also retained high chemical purity supporting improved stability.

It can be seen from the T¹ purity results of the isolated salt (Table 6 below) that the besylate salt from toluene showed high purity values before and after the stability study.

TABLE 6
Summary of purity before and after 40° C./75% RH for 1 week
Entry	Salt	ID	Purity T0/%	Purity T1/%
1	besylate	LJC-039-009-7	95.9	95.9

The results above show that the besylate salt form showed high purity and favourable stability results.

EXAMPLE 3

Scale up of the besylate salt to 100 mg was performed based on data in Example 2. Toluene was found to be the preferred solvent for isolating besylate salts.

Besylate Salt of Compound of Formula (I)

A scale up to 50 mg of input material was carried out in order to confirm whether or not the process would scale up, and to confirm that the material isolated was of the same crystalline form (Form 1) seen from the previous smaller scale experiment. Once the analysis confirmed the salt to be Form 1 and that the properties were in keeping with what was expected, another scale up was carried out with 100 mg of input material in order to carry out full characterisation and submit the sample for a 4 week stability study at 40° C./75% RH. Both the scaled up reactions were carried out in toluene with benzene sulphonic acid added as a solution in ethanol (1M).

Besylate Experimental Procedure

Compound of formula (I) free base (100 mg, batch 704-17) was charged to a vial and toluene (600 μl) was added at ambient temperature. To the solution benzene sulphonic acid (250 μl, 1M in ethanol) was added and the reaction mixture stirred for fifteen minutes, after which time a solid had precipitated from the solution which was filtered, washed with toluene and oven dried at 40° C. under vacuum. Analysis by XRPD showed the solid to be of identical powder pattern as other besylates generated, and the ¹H NMR confirmed salt formation due to significant peak shifts.

TABLE 7
				Onset	TGA			Chiral
			GVS	melt/	weight	Solubility	Chemical	purity/%
Entry	ID	salt	uptake/%	° C.	loss/%	mg/ml	purity/%	e.e
1	LJC-	besylate	2.0	201.3	4.9	8.3	97.1	94.4
	039-
	037-1

The enantiomeric excess for LJC-039-037-1 was only 94.4 therefore the result was compared to another batch of besylate (LJC-039-081-1) that was isolated under identical conditions. The enantiomeric excess of this batch was 99.1%.

Process Optimisation

To improve further yields of besylate salt (Form 1) four solvents were screened (isopropyl acetate, ethyl formate, methanol and acetone). In total eight 100 mg scale reactions were conducted in these solvents with the relevant acid added as stock solution in ethanol for comparison to previous experiments.

Compound of formula (I) (batch 704-38, 100 mg) dissolved in solvent (600 μl) at ambient. Acid (250 μl, 1M stock solution in ethanol) added and all reaction mixtures stood for 48 hours at ambient. The results are summarised in Table 8.

TABLE 8
Results of process optimisation experiments
							Purity post
Table	Lab book					Purity/	40° C./75% RH
entry	reference	Salt	Solvent	XRPD	Yield/%	% area	for 4 weeks
1	LJC-039-	besylate	acetone	Form 1	38	98.4	98.1
	067-2
2	LJC-039-	besylate	iPrOAc	Form 1	79	97.7	95.9
	067-4
3	LJC-039-	besylate	Ethyl	Form 1	40	98.6	98.3
	067-6		formate
4	LJC-039-	besylate	MeOH	Single	Not	98.1	Not recorded
	067-8			crystals,	recorded
				Form 2

All reactions except that of besylate formation in methanol showed Form 1. The methanol reaction was stored at 4° C. The data obtained confirmed anhydrous besylate 1:1, and a powder pattern of the material confirmed the existence of a new form (Form 2).

It was concluded from the study that solvents such as isopropyl acetate increased the purity of the salts, however reduced the recovery. Because the previous choice of solvent (ethyl acetate) gave high yielding salts with high purity values, it was decided to use ethyl acetate for the final scale up experiments.

Besylate (Form 1) 1 g Scale-Up

A 1 g formation of the besylate salt was carried out. This successfully produced 950 mg (70% yield) of Form 1. The liquors were highly coloured (yellow) and therefore seeded with a small amount of Form 1, to assist recovery. The liquors were stored at 4° C. for 16 hours. The solid obtained displayed a new powder pattern (Form 3). The solid was analysed by thermal analysis and variable temperature XRPD to confirm whether or not it was a true polymorph or a solvate. Interpretation of the analysis concluded it not to be a solvate from the ¹H NMR evidence, and the DSC showed two endothermic events confirmed by hostage microscopy (FIG. 3). It was interpreted that the seeds of Form 1 melted at 187° C., with Form 3 melting at 200° C. The reason that Form 1 was not identified by XRPD is that this is a less sensitive technique than microscopy.

Form 3 precipitates at a lower temperature to Form 1.

Characterisation was carried out on the polymorphs to propose the relationship between them.

TABLE 9
Thermal data of besylate forms
Entry	ID	Form	Onset of Melt/° C.	ΔH/Jg−1
1	LJC-039-081-1	1	201	56
2	LJC-039-067-8	2	180	73
3	LJC-039-081-2	1, 3	187, 200	7.6, 37

The lower melting point of the small amount of Form 1 present in LJC-039-081-2 can be potentially attributed to lower purity (97.2% compared with 97.9% in LJC-039-081-1).

FIG. 4 shows the DSC of besylate forms 1 (solid) and 2 (dashed).

FIG. 5 shows the DSC of besylate forms 1 (solid) and 3 (dotted and dashed).

EXAMPLE 4

Salt Stability Studies

TABLE 10
Summary Table of salt purities after 4 week stability study
Sample ID	salt	T0	T1	T2	T3	T4
LJC-039-037-1	besylate	97.1	97.3	97.4	96.7	96.7

Crystalline samples of besylate were stored at 40° C./75% RH for a total of four weeks and samples were taken for HPLC every seven days. The besylate hplc purity remained consistent up until T³ when it reached 96.7%. This value did however remain consistent to T⁴.

The hplc chromatographs for the besylate salt form are shown in FIG. 6 for time points week zero and week four.

It is suspected that the dominant peak prior to that of the parent is from contamination as the λ_max does not match the λ_max of the parent peak. It is also absent from the impurity profile of T¹, T², T³ and T⁴.

It can be seen from the powder patterns of the salts pre and post humidity studies that there are no changes in form.

FIG. 7 shows XRPD comparing LJC-039-037-1 (besylate salt) pre and post 4 week stability study.

EXAMPLE 5

Polymorphism Investigation

In order to determine the propensity of besylate salts to exhibit polymorphism, a maturation experiment was set up using thirty solvents (fifteen neat plus their 2.5% aqueous counterparts). The solid was slurried in various solvents (see Table 11) for one week on a heat/cool cycle from ambient to 60° C. After one week the slurries were evaporated and the solids analysed by XRPD and HPLC.

TABLE 11
Results of polymorphism investigation
for besylate (LJC-039-058-2)
Entry	solvent	XRPD post 1 week	HPLC purity/% area
1	acetone	Form 1	97.5
2	THF	Form 1	97.6
3	IPA	amorphous	97.1
4	MtBE	Form 1	97.7
5	DCM	amorphous	97.4
6	EtOH	oil	not analysed
7	MEK	Form 1	97.2
8	1,4-Dioxane	Form 1	97.2
9	iPrOAc	Form 1	97.5
10	DMF	oil	not analysed
11	MeCN	Form 1	94.3
12	nBuOH	oil	not analysed
13	nPrOH	oil	not analysed
14	MIBK	Form 1	97.7
15	MeOH	oil	not analysed
16	2.5% aq acetone	Form 1	96.8
17	2.5% aq THF	amorphous	93.3
18	2.5% aq IPA	Form 1	76.1
19	2.5% aq MtBE	oil	not analysed
20	2.5% aq DCM	Form 1	97.4
21	2.5% aq EtOH	oil	not analysed
22	2.5% aq MEK	Form 1	93.9
23	2.5% aq 1,4-Dioxane	Form 1	86
24	2.5% aq iPrOAc	oil	not analysed
25	2.5% aq DMF	oil	not analysed
26	2.5% aq MeCN	Form 1	93.3
27	2.5% aq nBuOH	oil	not analysed
28	2.5% aq nPrOH	oil	not analysed
29	2.5% aq MIBK	Form 1	97.3
30	2.5% aq MeOH	oil	not analysed
starting hplc purity 97.7%

The maturation study using the besylate salt revealed no new forms. The purity results post maturation show that those slurried in acetonitrile, aqueous THF, aqueous IPA aqueous MEK, aqueous dioxane and aqueous acetonitrile degraded. This suggests that the besylate salt (Form 1) has good solution stability in neat organic solvents at high temperature.

Investigating New Forms of Besylate

Although no new forms of the besylate salt were seen from the maturation study, a new form was seen when crystals were grown in methanol. The single crystals obtained from methanol were ground in order to obtain a powder pattern. This pattern turned out to be different from Form 1. A repeat experiment was carried out in order to obtain a further supply of Form 2. It was only possible to isolate Form 2 from precipitation over 16 hours from the liquors, opposed to allowing the solvent to evaporate, this gave Form 1. Interestingly two habits were present; needles and blocks. Both showed the same powder pattern as the needle habit that was used for single crystal structure determination.

Full analysis was carried out on Form 2. It had been concluded that it was a true polymorph as the single crystal data confirmed anhydrous besylate 1:1.

FIG. 8A shows an XRPD comparison of besylate Form 1 and 2. There is an obvious difference between Form 1 (trace 1) and Form 2 (trace 2). As can be seen from the two powder patterns, both forms are very different. Thermal analysis was carried out to compare the melting points of the two forms and also thermodynamic solubility measurements recorded.

FIG. 8B shows overlays of Form 1 and 2. Form 1 and 2 show one endothermic event (melting).

Form 3 was identified when a second crop was isolated from the liquors of LJC-039-081-1 (the 1 g scale-up reaction). Analysis was carried out in order to determine whether or not it was a solvate and how the forms interconvert.

FIG. 9A shows an XRPD comparison of besylate Form 1 and 3. FIG. 9B shows overlays of Form 1, and 3.

Form 1 shows one endothermic event (melting), whereas Form 3 shows two events. Hotstage microscopy on Form 3 clearly shows two melts within 20° C. of each other. It is postulated that a small amount of the lower melting polymorph is present as it was not picked up in variable temperature XRPD, which is a less sensitive technique. It is quite possible that the first endothermic event represents Form 1 as it was used to seed the liquors that Form 3 was isolated from.

The solubility data shows that all three forms have very similar aqueous solubilities of 7.8 to 8.3 mg/ml at pH 3.

Besylate Salt Form 4

The release batch of besylate salt Form 1 (LJC-039-083-1) was of high purity (97.6%), but contained a small amount of impurity carried through from the free base (0.78%, 11.9 min RT). This impurity was observed in the DSC experiment showing an endothermic transition (onset at 130° C.). The peak was confirmed as having an unrelated λmax to that of the parent peak.

A 100 mg sample was taken for a re-crystallisation attempt from 40% isopropyl acetate/ethanol. The re-crystallisation was carried out traditionally by dissolving the salt in the minimum amount of hot solvent, then cooling slowly to ambient to yield a precipitate. The dried solid was analysed by XRPD which indicated a new form, and with thermal analysis and ¹H NMR it was confirmed to be a polymorph and not a solvate. FIG. 10 shows DSC of LJC-039-086-1.

The salt screen investigations have shown that compound of formula (I) forms many salts within the appropriate pKa range, and that they are easily isolated from a range of solvents. From full characterisation of the salts, it has been determined that the besylate salts have good stability with respect to humidity. It has been concluded that there are two polymorphic forms of besylate. Form 3 came from the second crop of LJC-039-081-1 liquors after seeding with Form 1. Form 4 has been observed after a re-crystallisation of Form 1 was carried out from 40% isopropyl acetate/ethanol.

Full analytical data is shown in FIGS. 11-14 below.

Experimental Methods for Examples 2-5

EXAMPLE 2

Compound of formula (I) (5 mg/well) was dissolved in solvent¹ (30 μl) in HPLC vials. To the solutions, benzene sulphonic acid (11.4 μl, 1M in ethanol) was added and the reaction mixtures stood overnight at ambient. Those vials that contained solid were dried at 40° C. under vacuum, and those that remained as solutions were concentrated by evaporation and then treated with heptane. Those that precipitated were dried as mentioned, and those that oiled were stored at 4° C. ¹Ethanol, toluene and acetonitrile

Besylate Form 1 Scale Up

Compound of formula (I) (100 mg) dissolved in ethyl acetate (600 μl) and benzene sulphonic acid (250 μl, 1M in ethanol) added. Precipitation occurred instantly and the reaction mixture was stirred for 24 hours at ambient. The solid was filtered, washed with ethyl acetate and oven dried at 40° C. under vacuum for 16 hours.

Analysis Methods

Differential Scanning Calorimetry (DSC)

DSC data was collected on a TA instrument Q1000 equipped with a 50 position autosampler. The energy and temperature calibration standard was indium. Samples were heated at a rate of 10° C./min between 25 and 350° C. A nitrogen purge at 30 ml/min was maintained over the sample.

Between 0.5 and 3 mg of sample was used, unless otherwise stated, and all samples ran in a pin holed aluminium pan.

Thermogravimetric Analysis (TGA)

TGA data was collected on a TA Instrument Q500 TGA, calibrated with Alumel and running at scan rates of 10° C./minute. A nitrogen purge at 60 ml/min was maintained over the sample.

Typically 5-10 mg of sample was loaded onto a pre-tared platinum crucible unless otherwise stated.

NMR

All spectra were collected on a Bruker 400 MHz equipped with autosampler. Samples were prepared in d₆-DMSO, unless otherwise stated.

XRPD (X-Ray Powder Diffraction)

Bruker AXS C2 GADDS Diffractometer

X-ray powder diffraction patterns for the samples were acquired on a Bruker AXS C2 GADDS diffractometer using Cu Kα radiation (40 kV, 40 mA), automated XYZ stage, laser video microscope for auto-sample positioning and a HiStar 2-dimensional area detector. X-ray optics consists of a single Göbel multilayer mirror coupled with a pinhole collimator of 0.3 mm.

Beam divergence, i.e. the effective size of the X-ray beam on the sample, was approximately 4 mm. A θ-θ continuous scan mode was employed with a sample to detector distance of 20 cm which gives an effective 28 range of 3.2-29.8°. A typical exposure time of a sample would be 120 s.

Samples run under ambient conditions were prepared as flat plate specimens using powder as received without grinding. Approximately 1-2 mg of the sample was lightly pressed on a glass slide to obtain a flat surface. Samples run under non-ambient conditions were mounted on a silicon wafer with heat conducting compound. The sample was then heated to the appropriate temperature at ca. 20° C./minute and subsequently held isothermally for ca 1 minute before data collection was initiated.

Purity Analysis:

Chemical Method

Purity analysis was performed on a HP1100 Agilent:

Method: Gradient, Reverse Phase

Method Duration/min: 34

Column: Phenomenex Gemini C18 5 μm (2.0×50 mm) (Guard cartridge Phenomenex
Gemini C18 guard cartridge 2×4 mm)

Column Temperature/° C.: 40

Injection/μl: 5

Flow Rate ml/min: 0.8

Detection: UV

Wavelength/nm: 255 (bandwidth of 90 nm), 240 (bandwidth of 80 nm), 254 (bandwidth of 8 nm)
Phase A: 2 mmol NH₄HCO₃ (adjusted to pH10 with NH₃ solution)
Phase B: acetonitrile

Timetable:

Time/Min	% A	% B
0	90	10
25	10	90
28.8	10	90
29	90	10
34	90	10

Chiral Method

Purity analysis was performed on a Gilson HPLC system:

Method: Isocratic, Normal Phase

Method Duration/min: 50

Column: Diacel Chrialcel OJ-H (5 μm) 4.6×250 mm (Guard cartridge Diacel Chrialcel OJ-H analytical guard cartridge 5 μm 4.0×10 mm)

Column Temperature/° C.: 40

Injection/μl: 10

Flow Rate ml/min: 1.0

Detection: UV

Wavelength/nm: 225 (single wavelength detector)
Phase A: hexane
Phase B: ethanol

Timetable:

Time/Min	% A	% B
0	93	7

Gravimetric Vapour Sorption (GVS) Studies

All samples were run on a Hiden IGASorp moisture sorption analyser running CFRSorp software. Sample sizes were typically 10 mg. A moisture adsorption desorption isotherm was performed as outlined below (2 scans giving 1 complete cycle). All samples were loaded/unloaded at typical room humidity and temperature (40% RH, 25° C.). All samples were analysed by XRPD post GVS analysis. The standard isotherm was performed at 25° C. at 10% RH intervals over a 0-90% RH range unless otherwise stated.

Scan 1	Scan 2
Adsorption	Desorption	Adsorption
40	85	10
50	75	20
60	65	30
70	45	40
80	35
90	25
	15
	5
	0

Solubility

This was measured by suspending sufficient compound in 0.25 ml of solvent (water) to give a maximum final concentration of 10 mg/ml of the parent free form of the compound. The suspension was equilibrated at 25° C. for 24 hrs followed by a pH check and filtration through a glass fibre C 96 well plate. The filtrate is then diluted down 101×. Quantitation was by HPLC with reference to a standard dissolved in DMSO at approx 0.1 mg/ml. Different volumes of the standard, diluted and undiluted tests were injected. The solubility was calculated by integration of the peak area found at the same retention time as the peak maximum in the standard injection. If there is sufficient solid in the filter plate the XRPD is normally checked for phase changes, hydrate formation, amorphization, crystallization etc.

1: TABLE
Time/min	% Phase A	% Phase B
0.0	95	5
1.0	80	20
2.3	5	95
3.3	5	95
3.5	95	5
4.4	95	5

pKa Determination

pka determination was performed on a Sirius GlpKa instrument with D-PAS attachment. Measurements were made by potentiometric titration in MeOH:H2O mixtures at 25° C. The titration media was ionic strength adjusted with 0.15M KCl. The values found in the MeOH:H₂O mixtures were extrapolated to 0% co-solvent via a Yasuda-Shedlovsky extrapolation.

Hot Stacie Microscopy

Hot stage microscopy was studied using a Leica LM/DM polarised microscope combined with a Mettler-Toledo MTFP82HT hot-stage in the temperature range 25-350° C. with typical heating rates in the range 10-20° C./min. A small amount of sample was dispersed onto a glass slide with individual particles separated as well as possible. Samples were viewed under normal or cross-polarised light (coupled to a λ false-colour filter) with a ×20 objective lens.

Chiral Purity Method

System Setup

Pump: Gilson 322 binary pump

Detector: Gilson 152 UVN is

Autosampler: Gilson 233XL rack+Gilson 402 dual syringe pump
Column oven: Phenomenex Thermasphere TS-130
Software: Gilson Unipoint LC software

Column: Daicel Chiralcel OJ-H, 5 μm, 4.6×250 mm

Guard column: Daicel Chiralcel OJ-H analytical guard cartridge, 5 μm, 4.6×10 mm

HPLC Conditions

Channel A: Hexane (93%)

Channel B: Ethanol (7%)

Flow rate: 1.0 ml/min
Detector wavelength 225 nm

Column Temperature: 40° C.

Run time: 50.0 mins

Sample Conditions

Approximately 0.2 mg of sample was dissolved in the appropriate volume of Hexane:Ethanol 1:1 v/v to give a 0.2 mg/ml solution. This was capped and placed on a vortex mixer at high speed for a duration of ˜15 seconds. If solid remained at this point, then the sample vial was sonicated for approximately 10 seconds followed by a further 10 to 15 seconds on the vortex mixer. 10 μl was injected onto the HPLC system. Samples were injected in duplicate following an initial duplicate injection of Hexane:Ethanol 1:1 v/v as a blank.

EXAMPLE 5

Pharmacological Test Example

The anaesthetic and sedative effects of the besylate salt Form 1 of the present invention was evaluated. The besylate (benzenesulphonic acid) salt was dissolved in physiological saline for administration of the test composition to the animal. The test composition was administered to mice, placed in individual Plexiglas cages (20×10×10 cm). Mice were injected with either vehicle or test substance by the intravenous route. The latency to sleep and the duration of anaesthesia (maximum: 90 minutes after test-substance administration) were recorded. Anaesthesia is indicated by loss of the righting reflex (LRR). The righting reflex test was performed as soon as the animals appear sedated, approximately every 20-30 seconds. Once the righting reflex is absent, duration of loss of righting reflex was measured by testing for the return of the righting reflex approximately every 20-30 seconds thereafter. Eight mice were studied per group and the test was performed blind. Results from the study are given in the table below.

TREATMENT	NUMBER	LATENCY TO LRR	LRR DURATION (##)
(mg/kg)	OF MICE	(min)	(min)
i.v.	WITH LRR	mean ± s.e.m. (#)	mean ± s.e.m. (#)	p value
Vehicle	0	—	0.0 ± 0.0	—
CNS 7056X besylate	2	—	1.7 ± 1.3 NS	0.1441
(20.4)
CNS 7056X besylate	5 +	3.0 ± 0.2	4.9 ± 1.6 *	0.0106
(27.2)
CNS 7056X besylate	6 ++	1.8 ± 0.2	6.0 ± 1.9 **	0.0038
(34)
CNS 7056X besylate	6 ++	1.6 ± 0.5	7.3 ± 2.5 **	0.0038
(40.8)
Mann-Whitney U test:
NS = Not Significant;
* p < 0.05;
** p < 0.01
Fisher's Exact test (number of mice with LRR):
no indication = not significant;
+ = p < 0.05;
++ = p < 0.01
(#): not calculated if n < 3
(##): maximum = 90 minutes after injection

The results in the above table show that the besylate salt Form 1 has a short latency to loss of righting reflex and therefore a short induction time to anaesthesia in the animals. Additionally the mice recover rapidly from anaesthesia as indicated by the short duration of loss of righting reflex. Thus, this compound can provide rapid induction and recovery from anaesthesia.

EXAMPLE 6

Additional Conditions for Crystallisation of Forms 2, 3, and 4

Additional conditions were tested in an attempt to reproduce the previously reported crystallisations of Forms 2, 3 and 4. However, the reported scales were substantially reduced and the methodology modified accordingly, as described below.

Form 2

5 mg of solid was dissolved in 25 ul of methanol and 10 ul of ethanol added; the solution was then chilled at 4° C. for 3 days.

Form 3

Three variants were attempted:

5 mg of solid was dissolved in 50 ul of ethanol and 120 ul of ethyl acetate added; the solution was then chilled at 4° C. for 3 days.

10.1 mg of solid was dissolved in 300 ul of ethanol and 120 ul of ethyl acetate added; the solution was then chilled at 4° C. for 3 days.

2.5 mg of solid was dissolved in 50 ul of ethanol in a silanized vial and 100 ul of ethyl acetate added; the solution was then chilled at 4° C. for 3 days.

Form 4

Three variants were attempted:

A warmed (70° C.) mixture isopropyl acetate:ethanol (40%:60% v/v) was added to 5 mg of warmed solid in 20 ul aliquots until the solid dissolved (60 ul of solvent mixture in total); the solution was then allowed to cool slowly to ambient in a thermostated waterbath initially at 70° C. over a period of hours.

5 mg of solid was dissolved in 180 ul of warmed (50° C.) isopropyl acetate:ethanol (40%:60% v/v) solvent and the solution allowed to cool slowly to ambient in a thermostated waterbath (initially at 50° C.) over a period of hours.

5 mg portion of solid was dissolved in 100 ul of warmed (50° C.) isopropyl acetate:ethanol (40%:60% v/v) solvent in a silanized vial and the solution allowed to cool slowly to ambient in a thermostated waterbath (initially at 50° C.) over a period of hours.

Each of the crystallisations yielded solid material with blade and plate-like habits, with the Form 4 crystallisations also yielding needle-like material.

EXAMPLE 7

Characterisation of Compound of Formula (I) Besylate

Compound of formula (I) besylate is chiral and assumed to be of the single enantiomeric form below, i.e. the S enantiomer (consistent with the subsequently determined crystal structures):

The heterocyclic structure contains a basic Nitrogen in the imidazole ring (pKa of ca. 5), and a weaker basic Nitrogen in the pyridyl ring (pKa of ca. 2). The imidazole-Nitrogen will typically be protonated in the presence of the strongly acidic besylate (pKa ca. −0.6) in aqueous solution, with the pyridyl-Nitrogen also potentially being protonated under conditions of excess besylate.

The neutral free base form (i.e. unprotonated) of the compound is expected to be somewhat lipophilic (log P_{octanol:water} ca. 4.0) and thus would prefer some lipophilic environments over aqueous ones. Moreover, it is likely to retain a degree of lipophillicity even when monoprotonated (log D_octan:water ca. 2 at pH 3), although the effect of the besylate counter-ion is likely to ameliorate this tendency through its inherent hydrophilicity. The degree of lipophilicity further diminishes for the diprotonated form (log D_octan:water ca. 0.6 at pH 0).

The compound also has an excess of Hydrogen bond acceptors and therefore will be suitably partnered by Hydrogen bond donating solvents. It is thus expected that the compound will prefer solubilisation in a range of polar organic solvents such as the alcohols, particularly those which provide a partially lipophillic, Hydrogen bond donating environment. This has been borne out by experimental evidence (details of solvents used are given in Example 8):

                       Observed solubility
Solvent                (mg/ml)
Formamide              350
Water                  2
Dimethyl sulphoxide    500
Dimethylacetamide      200
1,2-ethanediol         60
Dimethylformamide      300
Acetonitrile           >20
Methanol               400
2-ethoxyethanol        20
2,2,2-trifluoroethanol 1000
Ethanol                100
Acetone                2
Propan-1-ol            15
Propan-2-ol            4.8
2-methoxyethanol       167
Hexafluoropropan-2-ol  >700
Dichloromethane        <<0.3
Tetrahydrofuran        2.5
Methylbenzoate         2
Ethyl acetate          0.2
Chloroform             <<0.4
1,4-dioxan             1
Soluble (>5 mg/ml), partially soluble (2.5-5 mg/ml), partially insoluble (0.5-2.5 mg/ml, insoluble (<0.5 mg/ml).
Values quoted are approximate, but experimentally confirmed.

These results highlight the good solubility of the compound in a wide variety of polar organic solvents. In particular, 2,2,2-trifluoroethanol and hexafluoropropan-2-ol are both identified as extremely good solvents for this compound. This is consistent with the considerations discussed above, both solvents being strong Hydrogen bond donors. Likewise, the more substantially lipophilic solvents are identified as poor solvents and thence potential anti-solvents for crystallisations.

EXAMPLE 8

Compound of Formula (I) Besylate Crystallisations

Various conditions conducive to obtaining crystalline material of compound of formula (I) besylate Forms 1 and 2 are described. Crystallisation conditions which include alcohols or acetonitrile solvents as components, with their respectively compatible anti-solvents or co-solvents, are believed to provide the most promising conditions to yield useful crystalline material. Crystallisation using solvent/anti-solvent binary mixtures was primarily used. Crystallisations were performed by retarded evaporation from sub-saturated solutions of the compound in solvent/anti-solvent mixtures, at ambient and reduced (4° C.) temperature. Crystallisation was typically observed within 3-5 days of preparation.

Where sample quantity allowed, all crystallisation conditions were performed in duplicate in a glass 96-weliplate format; one half of each wellplate being used to duplicate the conditions in the other half of the wellplate. Cross-contamination between wells is minimised by design. All of the conditions tested behaved reproducibly in at least duplicate, most yielding solid material suitable for further analysis.

In all cases, equipment coming into contact with samples and crystallisation media were scrupulously cleaned with a variety of solvents and reagents before being bathed in ethanol and blown dry using copious evaporated nitrogen.

High quality solvents from commercial suppliers were employed, as described in Table 12.

		Cat.
Solvent	Supplier	No.	Batch No.	Grade	Purity
1,2-dichlorobenzene	Romil	H177	E558470	SpS	>99.8%
1,4-dimethylbenzene	Fluka	95682	429739/1	puriss	>99%
				p.a.
1,4-dioxan	Romil	H297	H540480	SpS	>99.9%
2,2,2-trifluoroethanol	Romil	H860	M538412	SpS	>99.9%
acetonitrile	Romil	H049	D531490	SpS	>99.9%
dimethylacetamide	Romil	H249	B540480	SpS	>99.9%
dimethylsulphoxide	Romil	H280	W530480	SpS	>99.9%
ethanol	Romil	H314	O533480	SpS	>99.8%
ethyl acetate	Romil	H346	T533480	SpS	>99.9%
methyl iso-butyl	Romil	H446	M539430	SpS	>99.9%
ketone
n-nonane	Romil	H568	O558450	SpS	>99.9%
pentylacetate	Fluka	46022	13248/1	puriss	>98.5%
				p.a.
propan-1-ol	Romil	H624	G531460	SpS	>99.9%
propan-2-ol	Romil	H625	O530480	SpS	>99.9%
tetrachloroethylene	Romil	H702	W536450	SpS	>99.9%
tetrahydrofuran	Romil	H718	B532470	SpS	>99.9%
Acetone	Romil	H031	E559470	SpS	>99.9%
Chloroform	Romil	H135	B554470	SpS	>99.9%
Dichloromethane	Romil	H202	O554460	SpS	>99.9%
Dimethylformamide	Romil	H253	T546460	SpS	>99.9%
Formamide	Romil	H351	Q537480	BioPure	>99.9%
Hexafluoropropan-2-ol	Romil	H359	H559470	SpS	>99.9%
Methylbenzoate	Fluka	12460	417868/1	purum	>98%
water	Romil	H950	D537480	SpS	>99.9%

Visual analysis of the resulting crystalline morphologies was achieved using a binocular microscope (ca. 10×-40× magnification) with digital camera attached, employing both transmitted and reflected lighting as appropriate.

Visual characterisation of the solid material is summarised in Table 14 below. A predominance of blade or tabular/plate morphologies, either as unique crystals or as spherulites, was observed. Over all, there was little morphological difference between the crystallisations performed at ambient temperatures and those at 4° C., with the exception of those with ethanol as solvent where the tendency for spherulite and interface type growth diminished with lowered temperature. It is notable that the use of anti-solvent can improve the quality of the crystalline material substantially.

Example images of the crystalline material observed are presented in FIG. 17. As illustrated in this Figure, acetonitrile has a tendency to produce spherulite growth, typically seen as a consequence of poor nucleation and thence growth from poor quality crystal surfaces. In contrast, 2-methoxyethanol has a tendency to produce unique crystals of blade/needle-like morphology.

There appears to be a general preference for Form 1 to crystallise from many of the conditions. However, it is notable that Form 2 has also been observed from several crystallisation conditions, including the scaled-down analogues for obtaining Forms 3 and 4 (described in Example 6). Form 2 is observed in conditions where there are extremes of either polarity (acetonitrile:water) or lipophillicity (n-nonane) or both (dimethyl sulphoxide: 1,2-dichlorobenzene). In general, the crystals of Form 2 were notable in their superior quality and distinctive well-formed plate/tabular habit.

Single Crystal X-ray Diffraction Cell Determinations

To provide corroborative evidence of the crystalline forms generated, the cell parameters of a number of crystals of suitable quality were determined using single crystal X-ray diffraction. Crystal unit cell parameters were determined using a Kappa CCD diffractometer with Mo radiation, the crystals mounted on a glass fibre with oil and held at 260K. The parameters for Form 1 and Form 2 have been determined as summarised in Table 13.

TABLE 13
Cell parameters determined for crystals
of compound of formula (I) besylate.
	Form 1	Form 2
Crystal State
	Solvent	2-methoxyethanol	ethanol
	Anti-solvent/Co-	pentyl acetate	ethyl acetate
	solvent
	Crystal Morphology	needle	plate
	Crystal Size (mm)	0.8 × 0.04 × 0.02	0.7 × 0.3 × 0.25
	Colour	colourless	colourless
Crystal Structure
	System	monoclinic	orthorhombic
	Unit Cell
	a (Å)	7.6868(1)	8.92130(10)
	b (Å)	29.2607(5)	11.1536(2)
	c (Å)	12.3756(3)	25.8345(4)
	α (°)	90	90
	β (°)	97.7880(8)	90
	γ (°)	90	90
	Volume (Å3)	2757.86(9)	2570.65(7)

The crystallisation results from solvent/co-solvent and solvent/anti-solvent conditions for compound of formula (I) beslyate with single crystal X-ray diffraction unit cell results are tabulated in Table 14.

TABLE 14
Experimental crystallisation results from solvent/co-solvent and solvent/anti-solvent conditions
for compound of formula (I) besylate, with single crystal X-ray diffraction unit cell results
(X-ray results for ambient crystallisations unless otherwise stated).
			X-ray
		Observed	Form
	Co/Anti-solvent	Crystallisations	(No & habit of
Solvent	(& conditions)	Habit	crystals)
methanol	ethanol (at 4° C., 3 days)	blades & plates	2 (hex, blade)
ethanol	ethyl acetate (at 4° C., 3	blades & plates	2 (4 plates)
	days)
ethanol	ethyl acetate	blades & plates	2 (6 plates)
isopropyl acetate	ethanol (70° C. → 20° C.)	blades, plates & needles	2 (2 plates)
isopropyl acetate	ethanol (50° C. → 20° C.)	blades & plates	2 (2 hex plates,
			2 plates, 2 blades)
ethanol	methyl isobutyl	tabular plates	2 (3 plates)
	ketone (at 4° C., 3 days,
	silanized vial)
ethanol	p-cymene (at 4° C., 3	plate & tabular	2 (2 tabular)
	days, silanized vial)
nonane	none (silanized vial)	blades & plates	2 (plate)
dimethylsulfoxide	1,2-dichlorobenzene	intergrown blades	2 (tabular)
		dendrite, one huge
		tabular
dimethylacetamide	methyl isobutyl	plate-like fragments	1 (blade)
	ketone
dimethylacetamide	tetrachloroethylene	intergrown blades	1 (2 blades)
acetonitrile	water	interface	2 (2 tabular)
acetonitrile	3-methylbutan-1-ol	triangular plates,	1 (blade)
		fragments & dendrite
acetonitrile	1,2-dichlorobenzene	spherulite blades	1 (2 blades)
acetonitrile	pentyl acetate	spherulite blades	1 (blade)
methanol	none	interface plates	2 (plate)
methanol	3-methylbutan-1-ol	triangular plates &	1 (2 blades)
		fragments
methanol	methyl isobutyl	fragments & blade	1 (blade)
	ketone
2,2,2-	1,2-dichlorobenzene	interface & blade	1 (trans, blade)
trifluoroethanol		opaque & translucent
		blades
2,2,2-	1,4-dimethylbenzene	plate-like fragments	1 (sph, plate)
trifluoroethanol
ethanol	methyl isobutyl	interface plates (5° C.:	1 (interface),
	ketone	tabular & plate)	2 (tabular)
ethanol	1,2-dichlorobenzene	interface plates, (5° C.:	2 (plate)
		needles)
ethanol	tetrachloroethylene	interface (5° C.:	2 (blade 4° C.)
		hexagonal tabular)
ethanol	1,4-dimethylbenzene	interface blades	1 (blade)
propan-1-ol	none	plate-like fragments	1 (plate)
propan-1-ol	1,2-dichlorobenzene	interface	1 (blade)
propan-1-ol	tetrachloroethylene	plate-like fragments &	1 (blade)
		interface
propan-2-ol	1,2-dichlorobenzene	fan needles & dendrite	1 (blade)
propan-2-ol	n-nonane	blades, needles &	1 (needle)
		spherulite needles
2-methoxy ethanol	water	blade	1 (2 blades)
2-methoxy ethanol	pentyl acetate	needles	1 (blade)
2-methoxy ethanol	1,4-dimethylbenzene	blades & needles	1 (blade)
2-methoxy ethanol	n-nonane	blades & dendrite	1 (blade)
tetrahydrofuran	water	plate	1 (plate)
tetrahydrofuran	3-methylbutan-1-ol	intergrown blades	1 (plate)
tetrahydrofuran	1,2-dichlorobenzene	prismatic tabular,	2 (3 tabular)
		fragments, powder
tetrahydrofuran	ethyl acetate	dendrite, interface	2 (plate 4° C.)
tetrahydrofuran	isopropyl acetate	intergrown plates &	1 (plate)
		intergrown blades
tetrahydrofuran	1,3-dimethylbenzene	intergrown blades	1 (blade)
1,4-dioxane	pentyl acetate	triangular plates, some	1 (2 tri plate)
		part of spherulite
1,4-dioxane	1,4-dimethylbenzene	blade	1 (blade)

A variety of crystals of suitable quality for full single crystal X-ray diffraction crystal structure determination were achieved and the full structure obtained for Forms 1 and 2. These crystal structures are reported in Examples 9 and 10.

EXAMPLE 9

Crystal Structure of Form 1

Crystals of compound of formula (I) besylate grown from a 2-methoxyethanol:pentyl acetate solution which have a needle habit, are imaged in FIG. 17.

A single needle habit crystal (ca. 0.8×0.04×0.02 mm in size) was selected and its cell parameters determined at 260K and then at 190K. No transition was observed on lowering the temperature between 260-190K. The structure analysed here is for the data at 190K; parameters of the crystal and the X-ray diffraction refinement are given in Table 15.

TABLE 15
Data of the 2-methoxyethanol: pentyl acetate grown
crystal of compound of formula (I) besylate, Form 1.
Crystal State
Code                             CNS7056 besylate
Solvent                          2-methoxyethanol
Anti-solvent/Co-solvent          pentyl acetate
Crystal Morphology               needle
Crystal Size (mm)                0.8 × 0.04 × 0.02
Colour                           colourless
Crystal Structure
Formula                          C54H50Br2N8O10S2
Formula Weight                   1194.98
System                           monoclinic
Space Group                      P 21
Unit Cell
a (Å)                            7.6868(1)
b (Å)                            29.2607(5)
c (Å)                            12.3756(3)
α (°)                            90
β (°)                            97.7880(8)
γ (°)                            90
Volume (Å3)                      2757.86(9)
Z (No. molecules in unit)        2
Z′ (No. molecules in asymmetric unit) 2
Density (g cm3)                  1.439
Absorption μ [MoKα] (mm−1)       1.610
F(000)                           1224
Data Collection
Temperature, (K)                 190
Instrument                       Kappa CCD diffractometer
Scan Type                        ω
Absorption Correction Type       multi-scan
No. of Measured Reflections      9868
No. of Independent Reflections   9848
θ min/max (°)                    1.80/27.49
h min/max                        −9/9
k min/max                        −37/36
l min/max                        −15/15
Refinement
Refinement On                    F
I/σ(I) Cut-off                   3
No. of Used Reflections          6821
No. of Parameters                686
R factor (%)                     6.34
Rw factor (%)                    6.39
S                                1.00
Δρ(min) Å-3                      −0.8
Δρ(max) Å-3                      0.8
Max Shift/Error                  0.0005
Flack Parameter                  0.027(11)

The content of the asymmetric unit is displayed in FIG. 18. It consists of two independent molecules of the compound and two independent besylate counter ions. Each compound has the imidazole-Nitrogen protonated.

The Flack “Enantiopole” parameter was determined as 0.03(1) and thus the stereochemistry of the structures depicted here are well established and are consistent with the purported stereochemistry for the compound:

Crystallographic co-ordinates and other relevant data are tabulated in the form of a SHELX file in Table 17.

The conformational disorder can be represented (in first approximation) by the “thermal ellipsoids” of the atomic positions, as presented on FIG. 19. It can be seen that the major regions of disorder lie in the methyl groups and in the besylate.

The difference between the two independent molecules comes mainly from the ester chains as seen in FIG. 20. One molecule has the ester chain being coplanar with the imidazole ring, whereas the other molecule has the ester chain being orthogonal.

The conformation of the ester chains are different to that adopted in Form 2 (FIG. 21). The orthogonal conformation observed in Form 1 bears the greatest similarity to that found in Form 2.

The two independent besylates have staggered conformations (FIG. 22). No substantial differences in bond lengths are apparent.

One besylate adopts the conformation observed for the besylate in Form 2 (FIG. 23).

The resolved crystal structure, viewed along the crystallographic a, b and c axes, is illustrated in FIG. 24a, b and c respectively. FIG. 25 summarises the shortest contacts observed in the crystal packing.

Each compound interacts with the two independent besylates. In particular, a short distance (hydrogen-bond type) is established between one oxygen atom of one besylate and the protonated nitrogen of the imidazole ring of the compound. The second independent compound interacts similarly, but with the second independent besylate.

Other close contacts (C—O, H—O) are observed between the compounds and the besylates mainly in the vicinity of the imidazole and pyridyl ring. Some close contacts are also observed between the two compounds themselves (Br—N, C—C, O—H) and the two besylate themselves (O—H contacts) but to a lesser extent for the latter.

Using the crystal structure determined experimentally, a powder diffraction pattern for Form 1 has been calculated using CrystalDiffract® (CrystalDiffract is a registered TradeMark of CrystalMaker Ltd) and is depicted in FIG. 26. This powder pattern matches the experimental powder pattern reported for Form 1.

EXAMPLE 10

Crystal Structure of Form 2

A crystal of compound of formula (I) besylate Form 2, which has a plate habit, is imaged in FIG. 27.

A single plate habit crystal (ca. 0.7×0.30×0.25 mm in size) was selected and its cell parameters determined at 260K then at 190K. No transition was observed on lowering the temperature between 260-190K. The structure analysed here is for the data at 190K; parameters of the crystal and the X-ray diffraction refinement are given in Table 16.

TABLE 16
Data of the ethanol:ethyl acetate grown crystal
of compound of formula (I) besylate, Form 2.
Crystal State
Code                             CNS7056 besylate
Solvent                          ethanol
Anti-solvent/Co-solvent          ethyl acetate
Crystal Morphology               plate
Crystal Size (mm)                0.7 × 0.30 × 0.25
Colour                           colourless
Crystal Structure
Formula                          C27H25Br1N4O5S1
Formula Weight                   597.49
System                           Orthorhombic
Space Group                      P 212121
Unit Cell
a (Å)                            8.92130(10)
b (Å)                            11.1526(2)
c (Å)                            25.8345(4)
α (°)                            90
β (°)                            90
γ (°)                            90
Volume (Å3)                      2570.65(7)
Z (No. molecules in unit)        4
Z′ (No. molecules in asymmetric unit) 1
Density (g cm3)                  1.544
Absorption μ [MoKα] (mm−1)       1.727
F(000)                           1224
Data Collection
Temperature, (K)                 190
Instrument                       Kappa CCD diffractometer
Scan Type                        ω
Absorption Correction Type       multi-scan
No. of Measured Reflections      5750
No. of Independent Reflections   5727
θ min/max (°)                    5.15/27.48
h min/max                        −11/11
k min/max                        −14/14
l min/max                        −33/33
Refinement
Refinement On                    F
I/σ(I) Cut-off                   3
No. of Used Reflections          4067
No. of Parameters                344
R factor (%)                     3.85
Rw factor (%)                    3.66
S                                1.12
Δρ(min) Å−3                      −0.6
Δρ(max) Å−3                      0.5
Max Shift/Error                  0.0003
Flack Parameter                  0.011(9)

The content of the asymmetric unit is displayed in FIG. 28. It consists of one independent molecule of the compound and one independent besylate. The compound has the imidazole-Nitrogen protonated.

The Flack “Enantiopole” parameter was determined as 0.011(9) and thus the stereochemistry of the structures depicted here are well established and are consistent with the purported stereochemistry for the compound. Crystallographic co-ordinates and other relevant data are tabulated in the form of a SHELX file in Table 18.

The conformational disorder can be represented (in first approximation) by the “thermal ellipsoids” of the atomic positions, as presented on FIG. 29. It can be seen that the major regions of disorder lie in the besylate.

As discussed above, the conformation of the ester chain in Form 2, depicted in FIG. 30, is different to that adopted in Form 1.

However, the conformation of the besylate is similar to the one observed for one of the besylate in Form 1 (FIG. 31).

The resolved crystal structure, viewed along the crystallographic a, b and c axes, is illustrated in FIG. 32a, b and c respectively with FIG. 33 summarising the shortest contacts observed in the crystal packing. The compound establishes a short contact (hydrogen-bond type) with one oxygen atom of the besylate through its protonated nitrogen of the imidazole ring. Other short contacts (C—C, C—O, H—O) are observed between the compound and the besylate through the imidazole ring.

Some close contacts are also observed between the two compounds themselves (Br—C, C—C, O—C, O—H), most of which are via the ester chain. There are no close contacts between the besylate themselves.

Using the crystal structure determined experimentally, a powder diffraction pattern for Form 2 has been calculated using CrystalDiffract® (FIG. 34). This powder pattern matches the experimental powder pattern reported for Form 2.

TABLE 17
Crystallographic co-ordinates and other relevant data tabulated in the
form of a SHELX File for Compound of formula (I) besylate Form 1.
TITL	12161316  Compound CNS7056 Form 1
CELL	0.71073 7.687 29.261 12.376 90.000 97.788 90.000
ZERR	2 0.0001 0.0005 0.0003 0.0000 0.0008 0.0000
LATT	−1
SYMM	−X, Y + 0.500, −Z
SFAC C	2.3100	20.8439	1.0200	10.2075	1.5886	0.5687
0.8650 =	51.6512	0.2156	0.0033	0.0016	1.15	0.7700
	12.0110
SFAC H	0.4930	10.5109	0.3229	26.1257	0.1402	3.1424
0.0408 =	57.7998	0.0030	0.0000	0.0000	0.06	0.3200
	1.0079
SFAC O	3.0485	13.2771	2.2868	5.7011	1.5463	0.3239
0.8670 =	32.9089	0.2508	0.0106	0.0060	3.25	0.7700
	15.9994
SFAC BR	17.1789	2.1723	5.2358	16.5796	5.6377	0.2609
3.9851 =	41.4328	2.9557	−0.2901	2.4595	1000.00	1.1000
	79.9040
SFAC N	12.2126	0.0057	3.1322	9.8933	2.0125	28.9975
1.1663 =	0.5826	−11.5290	0.0061	0.0033	1.96	0.7700
	14.0067
SFAC S	6.9053	1.4679	5.2034	22.2151	1.4379	0.2536
1.5863 =	56.1720	0.8669	0.1246	0.1234	53.20	1.1100
	32.0660
UNIT	108.	100.	20.	4.	16.	4.
S80	6	0.23964	0.43139	0.09908	11.00000	0.04634
0.03299 =	0.04052	0.00002	0.01880	−0.00340
O81	3	0.16028	0.39374	0.15143	11.00000	0.06864
0.04111 =	0.05255	−0.00210	0.02801	0.00002
O82	3	0.14598	0.47435	0.11207	11.00000	0.08099
0.03603 =	0.04614	0.00545	0.03373	−0.00236
O83	3	0.42589	0.43401	0.12925	11.00000	0.05754
0.08564 =	0.05198	−0.01536	0.01792	−0.00644
C84	1	0.20581	0.41866	−0.04324	11.00000	0.05949
0.04444 =	0.02903	0.00359	0.01728	0.00704
C85	1	0.03624	0.41100	−0.09142	11.00000	0.06649
0.10092 =	0.05586	0.01088	0.01751	0.00507
C86	1	0.00323	0.39810	−0.20187	11.00000	0.08670
0.14765 =	−0.02096	−0.03160	−0.00004
C87	1	0.14311	0.39209	−0.25693	11.00000	0.07916
0.11651 =	0.06238	−0.01696	0.00195	0.02481
C88	1	0.30473	0.39806	−0.20987	11.00000	0.09246
0.09710 =	0.04155	0.00157	0.01795	0.02685
C89	1	0.33456	0.41126	−0.10133	11.00000	0.05999
0.09817 =	0.07178	−0.01451	0.00886	0.02173
S90	6	0.68868	0.81145	0.51625	11.00000	0.04072
0.02869 =	0.05437	0.00158	0.00214	0.00223
O91	3	0.79129	0.77464	0.57315	11.00000	0.08025
0.03751 =	0.04867	−0.00213	−0.00954	0.01626
O92	3	0.52601	0.81933	0.56122	11.00000	0.04778
0.05360 =	0.06934	−0.00642	0.01702	0.00039
O93	3	0.78935	0.85213	0.50763	11.00000	0.07515
0.04369 =	0.05025	−0.01354	0.01764	−0.01547
C94	1	0.62446	0.78970	0.38130	11.00000	0.04232
0.04028 =	0.05049	0.00898	0.00929	0.00525
C95	1	0.74659	0.76959	0.32396	11.00000	0.06194
0.06998 =	0.03238	0.00341	−0.00103	0.00990
C96	1	0.69911	0.75023	0.22476	11.00000	0.12417
0.10337 =	0.03441	0.01537	0.02421	0.03314
C97	1	0.51941	0.75295	0.17732	11.00000	0.11897
0.11939 =	−0.01324	−0.00963	−0.00586
C98	1	0.40301	0.77268	0.23169	11.00000	0.06106
0.10242 =	0.00570	−0.01263	−0.00283
C99	1	0.45446	0.79193	0.33547	11.00000	0.05307
0.07089 =	0.00728	−0.00426	−0.01944
BR1	4	0.06011	0.52462	0.55140	11.00000	0.04153
0.05204 =	0.07369	−0.00524	0.02434	0.00670
C2	1	0.25757	0.50395	0.49005	11.00000	0.02832
0.04536 =	0.03350	−0.00752	0.01511	0.00763
C3	1	0.28921	0.45781	0.47911	11.00000	0.03135
0.03107 =	0.04579	0.00145	0.00221	−0.00479
C4	1	0.42954	0.44393	0.43174	11.00000	0.03767
0.03461 =	−0.00320	−0.00151	−0.00125
C5	1	0.54674	0.47556	0.39943	11.00000	0.03535
0.02939 =	0.03479	−0.00390	0.00647	0.00183
C6	1	0.51907	0.52242	0.41134	11.00000	0.04226
0.03479 =	0.04333	−0.00172	0.00236	0.00188
C7	1	0.37213	0.53602	0.45794	11.00000	0.03598
0.02793 =	0.04586	−0.00044	0.01652	0.00336
C8	1	0.64321	0.55824	0.38118	11.00000	0.03964
0.02453 =	0.02719	0.00516	0.00457	0.00373
C9	1	0.68998	0.59645	0.46059	11.00000	0.03743
0.03694 =	0.04454	−0.00375	0.01588	0.00649
N10	5	0.69097	0.58514	0.56581	11.00000	0.06070
0.03116 =	0.04918	−0.00640	0.02020	−0.00054
C11	1	0.74090	0.61847	0.63822	11.00000	0.06804
0.05787 =	0.04752	−0.00600	0.01695	−0.00669
C12	1	0.78515	0.66221	0.61053	11.00000	0.05480
0.04458 =	0.05526	−0.02125	0.01554	−0.00787
C13	1	0.77550	0.67229	0.50132	11.00000	0.04463
0.03102 =	0.05452	0.00407	0.01432	−0.00038
C14	1	0.73186	0.63955	0.42553	11.00000	0.04272
0.03021 =	0.04282	−0.00243	0.01499	0.00270
N15	5	0.71451	0.55972	0.29408	11.00000	0.04979
0.02502 =	0.03692	0.00975	0.01748	0.00775
C16	1	0.67500	0.52204	0.21324	11.00000	0.04463
0.02346 =	0.04948	−0.00464	0.01738	0.00561
C17	1	0.75857	0.47996	0.26673	11.00000	0.04549
0.02673 =	0.01954	−0.00693	0.00506	−0.00121
N18	5	0.70009	0.45973	0.35317	11.00000	0.03293
0.02806 =	0.02597	−0.00088	0.00321	0.00207
C19	1	0.81334	0.42409	0.39181	11.00000	0.03678
0.02848 =	0.03351	−0.00426	0.00585	0.00488
C20	1	0.93968	0.42402	0.32661	11.00000	0.03371
0.02802 =	0.03711	0.00202	0.00106	0.00680
N21	5	0.90585	0.45925	0.25315	11.00000	0.04775
0.03416 =	0.02231	−0.01051	0.01052	−0.00308
C22	1	0.79597	0.39511	0.48941	11.00000	0.03997
0.03711 =	0.04548	0.01039	0.00508	0.00197
C23	1	0.74788	0.53407	0.10940	11.00000	0.05650
0.04712 =	0.03514	0.00836	0.00449	0.00605
C24	1	0.68780	0.50047	0.01647	11.00000	0.08242
0.04077 =	0.03001	−0.00046	0.01385	0.00523
C25	1	0.71419	0.51690	−0.09234	11.00000	0.06429
0.06543 =	0.03392	0.00018	0.00559	−0.00499
O26	3	0.76261	0.55440	−0.11450	11.00000	0.12347
0.08282 =	0.04188	0.01501	0.01658	−0.04001
O27	3	0.65910	0.48459	−0.16756	11.00000	0.10340
0.06919 =	0.03191	0.00253	0.01824	−0.00449
C28	1	0.66642	0.49760	−0.27953	11.00000	0.19131
0.12699 =	0.01390	−0.01417	0.02134	−0.05279
BR51	4	1.06737	0.71057	0.98743	11.00000	0.03812
0.08781 =	0.06774	0.00566	−0.00531	0.00447
C52	1	0.84276	0.73306	0.93243	11.00000	0.03132
0.05952 =	0.03819	0.00358	0.00226	−0.00263
C53	1	0.81293	0.77906	0.93249	11.00000	0.04627
0.06820 =	0.03723	−0.00581	0.00481	−0.00474
C54	1	0.65043	0.79579	0.88269	11.00000	0.04551
0.03939 =	0.04858	−0.00084	0.00376	−0.01071
C55	1	0.51946	0.76552	0.84226	11.00000	0.04294
0.03573 =	0.03413	0.00062	0.00952	−0.00208
C56	1	0.54512	0.71765	0.84581	11.00000	0.02688
0.03659 =	0.04586	−0.00025	0.00561	0.00047
C57	1	0.71139	0.70186	0.88914	11.00000	0.03105
0.04840 =	0.04447	−0.00668	−0.00429	0.00504
C58	1	0.40956	0.68443	0.79765	11.00000	0.03348
0.02893 =	0.04334	0.00070	0.00351	0.00421
C59	1	0.38048	0.64253	0.86694	11.00000	0.03165
0.03488 =	0.04951	0.00002	0.00425	0.00528
N60	5	0.42879	0.64650	0.97247	11.00000	0.03542
0.05694 =	0.03178	0.00872	0.00154	0.00467
C61	1	0.38962	0.61026	1.03529	11.00000	0.04457
0.06338 =	0.05765	0.01416	0.00707	0.00171
C62	1	0.30187	0.57202	0.98967	11.00000	0.06548
0.04957 =	0.11303	0.03456	0.03582	0.00696
C63	1	0.25733	0.56863	0.88018	11.00000	0.07395
0.04664 =	0.09803	0.00115	0.01240	−0.01007
C64	1	0.29561	0.60475	0.81590	11.00000	0.08355
0.04152 =	0.05459	−0.00010	0.00128	−0.02308
N65	5	0.31344	0.68797	0.70771	11.00000	0.03846
0.03072 =	0.04952	−0.00160	0.00032	0.00597
C66	1	0.33129	0.72953	0.64125	11.00000	0.03574
0.02676 =	0.05519	0.00406	0.00580	0.00330
C67	1	0.26347	0.76733	0.70231	11.00000	0.03803
0.03316 =	0.04166	0.01528	0.00868	0.00029
N68	5	0.35122	0.78274	0.79764	11.00000	0.03387
0.03259 =	0.05055	0.00549	0.00427	0.00218
C69	1	0.24763	0.81583	0.84108	11.00000	0.05345
0.03305 =	0.04570	0.00005	0.02067	−0.00546
C70	1	0.09873	0.81841	0.77077	11.00000	0.04465
0.03799 =	0.06107	0.00794	0.01464	0.00936
N71	5	0.10819	0.78841	0.68720	11.00000	0.03892
0.03266 =	0.05306	0.00974	0.01063	0.00803
C72	1	0.30218	0.84064	0.94469	11.00000	0.08091
0.04934 =	0.08052	−0.01505	0.02392	−0.00661
C73	1	0.22541	0.72388	0.52948	11.00000	0.04039
0.05583 =	0.03295	0.00047	0.00724	−0.00165
C74	1	0.30154	0.68566	0.46508	11.00000	0.05896
0.05343 =	0.05504	−0.00576	0.00667	0.02016
C75	1	0.18003	0.67204	0.36587	11.00000	0.05296
0.05447 =	0.04241	0.00546	0.01355	0.00171
O76	3	0.06782	0.69497	0.31818	11.00000	0.05552
0.07543 =	0.05719	−0.00702	−0.00194	0.02108
O77	3	0.22119	0.62976	0.33149	11.00000	0.08466
0.04267 =	0.04376	−0.00714	0.00726	0.00488
C78	1	0.10717	0.61220	0.23887	11.00000	0.06302
0.09312 =	0.07465	−0.02449	0.02418	−0.00980
H611	2	10.42342	10.61111	11.10933	11.00000	0.06582
H621	2	10.27371	10.54835	11.03412	11.00000	0.09086
H631	2	10.20282	10.54235	10.84949	11.00000	0.08585
H641	2	10.26600	10.60396	10.74163	11.00000	0.07058
H661	2	10.45616	10.73494	10.63683	11.00000	0.04658
H701	2	10.00528	10.83765	10.77749	11.00000	0.05724
H721	2	10.20390	10.85662	10.96784	11.00000	0.10482
H722	2	10.39143	10.86250	10.93477	11.00000	0.10500
H723	2	10.34863	10.81975	11.00178	11.00000	0.10479
H731	2	10.22647	10.75279	10.49048	11.00000	0.05050
H732	2	10.10462	10.71635	10.53573	11.00000	0.05107
H741	2	10.41143	10.69632	10.44327	11.00000	0.06599
H742	2	10.32279	10.65905	10.51273	11.00000	0.06616
H571	2	10.73613	10.67093	10.88928	11.00000	0.04893
H531	2	10.89874	10.79871	10.96543	11.00000	0.05990
H541	2	10.63029	10.82681	10.87790	11.00000	0.05285
H161	2	10.54702	10.51731	10.19609	11.00000	0.04687
H201	2	11.03302	10.40374	10.33036	11.00000	0.03977
H221	2	10.90306	10.37871	10.51025	11.00000	0.06107
H222	2	10.77354	10.41394	10.54853	11.00000	0.06102
H223	2	10.70245	10.37370	10.47387	11.00000	0.06087
H231	2	10.71028	10.56434	10.08666	11.00000	0.05487
H232	2	10.87494	10.53365	10.12431	11.00000	0.05471
H241	2	10.56546	10.49241	10.01723	11.00000	0.06095
H242	2	10.75795	10.47323	10.02815	11.00000	0.06099
H111	2	10.74728	10.61186	10.71244	11.00000	0.06882
H121	2	10.81997	10.68398	10.66349	11.00000	0.06182
H131	2	10.79812	10.70154	10.48020	11.00000	0.05215
H141	2	10.72939	10.64544	10.35226	11.00000	0.04595
H71	2	10.35042	10.56684	10.46668	11.00000	0.04408
H31	2	10.21444	10.43638	10.50355	11.00000	0.04223
H41	2	10.44931	10.41280	10.42055	11.00000	0.04056
H891	2	10.44977	10.41481	9.93226	11.00000	0.09285
H881	2	10.39917	10.39332	9.75106	11.00000	0.09266
H871	2	10.12372	10.38356	9.66972	11.00000	0.10194
H861	2	9.88808	10.39388	9.76390	11.00000	0.11607
H851	2	9.94416	10.41466	9.94909	11.00000	0.08904
H951	2	10.86472	10.76918	10.35546	11.00000	0.06580
H961	2	10.78321	10.73544	10.18942	11.00000	0.10497
H971	2	10.48493	10.74055	10.10914	11.00000	0.10604
H981	2	10.28646	10.77378	10.20054	11.00000	0.08719
H991	2	10.37377	10.80653	10.37249	11.00000	0.07037
H781	2	10.14480	10.58182	10.22240	11.00000	0.11588
H782	2	10.11102	10.63197	10.17669	11.00000	0.11581
H783	2	9.98883	10.61082	10.25546	11.00000	0.11600
H711	2	10.01359	10.78308	10.62464	11.00000	0.05205
H211	2	10.98261	10.46785	10.19729	11.00000	0.04161
H281	2	10.62358	10.47180	9.67092	11.00000	0.11566
H282	2	10.59036	10.52501	9.70225	11.00000	0.11566
H283	2	10.79029	10.50514	9.71088	11.00000	0.11566

TABLE 18
Crystallographic co-ordinates and other relevant data tabulated in the
form of a SHELX File for Compound of formula (I) besylate Form 2.
TITL	1142055  Compound CNS7056 form 2
CELL	0.71073 8.921 11.154 25.834 90.000 90.000 90.000
ZERR	4 0.0001 0.0002 0.0004 0.0000 0.0000 0.0000
LATT	−1
SYMM	X + 0.500, −Y + 0.500, −Z
SYMM	−X, Y + 0.500, −Z + 0.500
SYMM	−X + 0.500, −Y, Z + 0.500
SFAC C	2.3100	20.8439	1.0200	10.2075	1.5886	0.5687
0.8650 =	51.6512	0.2156	0.0033	0.0016	1.15	0.7700
	12.0110
SFAC H	0.4930	10.5109	0.3229	26.1257	0.1402	3.1424
0.0408 =	57.7998	0.0030	0.0000	0.0000	0.06	0.3200
	1.0079
SFAC BR	17.1789	2.1723	5.2358	16.5796	5.6377	0.2609
3.9851 =	41.4328	2.9557	−0.2901	2.4595	1000.00	1.1000
	79.9040
SFAC N	12.2126	0.0057	3.1322	9.8933	2.0125	28.9975
1.1663 =	0.5826	−11.5290	0.0061	0.0033	1.96	0.7700
	14.0067
SFAC O	3.0485	13.2771	2.2868	5.7011	1.5463	0.3239
0.8670 =	32.9089	0.2508	0.0106	0.0060	3.25	0.7700
	15.9994
SFAC S	6.9053	1.4679	5.2034	22.2151	1.4379	0.2536
1.5863 =	56.1720	0.8669	0.1246	0.1234	53.20	1.1100
	32.0660
UNIT	108.	100.	4.	16.	20.	4.
BR1	3	−0.04819	−0.10880	−0.27710	11.00000	0.07032
0.03277 =	0.00144	−0.01238	−0.02224
C2	1	−0.15018	−0.21830	−0.32054	11.00000	0.02777
0.02177 =	−0.00009	−0.00209	−0.00471
C3	1	−0.17401	−0.18875	−0.37205	11.00000	0.02963
0.01861 =	0.02702	0.00623	0.00188	−0.00107
C4	1	−0.24491	−0.26965	−0.40362	11.00000	0.02825
0.02442 =	0.01718	0.00327	0.00106	−0.00145
C5	1	−0.29275	−0.37943	−0.38401	11.00000	0.02223
0.01822 =	0.01875	−0.00067	0.00141	0.00066
C6	1	−0.27139	−0.40894	−0.33163	11.00000	0.02028
0.01967 =	0.01926	0.00182	0.00105	−0.00153
C7	1	−0.20042	−0.32532	−0.29979	11.00000	0.02809
0.02763 =	0.01685	0.00206	0.00190	−0.00055
C8	1	−0.32197	−0.52600	−0.30927	11.00000	0.01670
0.02233 =	0.00135	−0.00476	−0.00144
C9	1	−0.39853	−0.52353	−0.25770	11.00000	0.01623
0.02317 =	0.00259	−0.00384	−0.00281
N10	4	−0.46099	−0.41943	−0.24363	11.00000	0.02251
0.02613 =	0.02353	−0.00189	0.00408	0.00155
C11	1	−0.52777	−0.41652	−0.19697	11.00000	0.02617
0.03441 =	0.02357	−0.00451	0.00365	0.00346
C12	1	−0.53610	−0.51390	−0.16425	11.00000	0.02740
0.04329 =	0.02040	−0.00335	0.00652	−0.00779
C13	1	−0.47518	−0.62062	−0.17997	11.00000	0.03584
0.03200 =	0.02405	0.00767	0.00645	−0.00687
C14	1	−0.40334	−0.62685	−0.22730	11.00000	0.02879
0.02223 =	0.02565	0.00090	0.00272	−0.00057
N15	4	−0.30040	−0.62781	−0.33049	11.00000	0.02151
0.02416 =	0.01713	0.00287	−0.00002	0.00182
C16	1	−0.21928	−0.62991	−0.38036	11.00000	0.02330
0.02286 =	0.01602	0.00057	0.00417	0.00450
C17	1	−0.32510	−0.57975	−0.41920	11.00000	0.02824
0.02308 =	0.01704	−0.00121	0.00336	−0.00285
N18	4	−0.36294	−0.46298	−0.41818	11.00000	0.02482
0.02037 =	0.01483	0.00150	−0.00070	0.00079
C19	1	−0.46920	−0.44117	−0.45641	11.00000	0.03022
0.02725 =	0.01634	0.00325	0.00039	−0.00224
C20	1	−0.49445	−0.54753	−0.47911	11.00000	0.03071
0.03401 =	0.00110	−0.00174	−0.00215
N21	4	−0.40440	−0.63226	−0.45591	11.00000	0.03619
0.02354 =	0.02146	−0.00463	0.00147	−0.00154
C22	1	−0.54310	−0.32298	−0.46595	11.00000	0.03636
0.03429 =	0.00778	−0.00982	−0.00011
C23	1	−0.15995	−0.75547	−0.39193	11.00000	0.03430
0.02640 =	0.01793	−0.00359	0.00177	0.00554
C24	1	−0.06166	−0.79435	−0.34621	11.00000	0.04707
0.03881 =	0.02350	0.00041	0.00034	0.01530
C25	1	0.06625	−0.87542	−0.35603	11.00000	0.03182
0.02650 =	0.00340	−0.00125	−0.00016
O26	5	0.17233	−0.88334	−0.32760	11.00000	0.03778
0.06570 =	0.03313	−0.01160	−0.01173	0.00417
O27	5	0.05245	−0.94265	−0.39885	11.00000	0.03130
0.03874 =	0.02467	−0.00799	−0.00330	0.01418
C28	1	0.17574	−1.02443	−0.40865	11.00000	0.05622
0.08123 =	0.03697	−0.01153	−0.00496	0.04396
S80	6	−0.94275	−0.52899	−0.49624	11.00000	0.03340
0.02679 =	0.02442	0.00000	0.00210	−0.00075
O81	5	−0.83867	−0.47114	−0.53020	11.00000	0.05118
0.08336 =	0.02297	−0.00622	−0.02476
O82	5	−1.08156	−0.46260	−0.49186	11.00000	0.04015
0.07788 =	0.05503	−0.01022	−0.00539	0.01721
O83	5	−0.97025	−0.65272	−0.50726	11.00000	0.13945
0.03230 =	0.06071	−0.01467	0.01447	−0.00725
C84	1	−0.86288	−0.52210	−0.43343	11.00000	0.02735
0.05893 =	0.02832	0.01509	0.00686	−0.00534
C85	1	−0.87781	−0.41462	−0.40588	11.00000	0.03763
0.08695 =	0.03855	−0.01799	0.00427	−0.00754
C86	1	−0.81420	−0.39965	−0.35764	11.00000	0.05438
0.16315 =	0.04455	−0.02905	0.00147	−0.02905
C87	1	−0.73766	−0.49241	−0.33773	11.00000	0.06202
0.20226 =	0.03510	−0.02105	−0.05062
C88	1	−0.71835	−0.60444	−0.36221	11.00000	0.04217
0.17120 =	0.11388	0.10762	−0.01320	−0.03729
C89	1	−0.78500	−0.61610	−0.41251	11.00000	0.03725
0.08786 =	0.05538	−0.00772	−0.01074
H891	2	9.22557	9.31210	9.56883	11.00000	0.08027
H881	2	9.33331	9.33306	9.65289	11.00000	0.13097
H851	2	9.06867	9.64846	9.57936	11.00000	0.06577
H861	2	9.17563	9.67239	9.66111	11.00000	0.10509
H161	2	9.86530	9.42517	9.62245	11.00000	0.02469
H111	2	9.42959	9.65626	9.81326	11.00000	0.03383
H121	2	9.41618	9.49292	9.86839	11.00000	0.03606
H131	2	9.51614	9.31066	9.84059	11.00000	0.03697
H141	2	9.64103	9.30191	9.76144	11.00000	0.03108
H231	2	9.89972	9.24922	9.57680	11.00000	0.03066
H232	2	9.75764	9.18723	9.60372	11.00000	0.03099
H241	2	9.87585	9.16237	9.67759	11.00000	0.04434
H242	2	9.97980	9.27746	9.67100	11.00000	0.04489
H281	2	10.15353	8.92912	9.56085	11.00000	0.08666
H282	2	10.18989	8.92278	9.62053	11.00000	0.08723
H283	2	10.26566	9.02166	9.58620	11.00000	0.08710
H201	2	9.44027	9.43682	9.49457	11.00000	0.03327
H221	2	9.36727	9.66624	9.51370	11.00000	0.05146
H222	2	9.52479	9.72860	9.51527	11.00000	0.05104
H223	2	9.43193	9.71611	9.56601	11.00000	0.05131
H41	2	9.73983	9.74902	9.56204	11.00000	0.02807
H31	2	9.85823	9.88568	9.61518	11.00000	0.03001
H71	2	9.81367	9.65791	9.73490	11.00000	0.02870
H871	2	9.30621	9.51762	9.69480	11.00000	0.13226
H211	2	9.59801	9.29339	9.53630	11.00000	0.03270

TABLE 19
Bond lengths for Compound of formula (I) besylate Form 1.
S80	O81	1.454(5)	Å	S80	O82	1.468(5)	Å
S80	O83	1.432(6)	Å	S80	C84	1.784(7)	Å
C84	C85	1.376(12)	Å	C84	C89	1.318(12)	Å
C85	C86	1.408(14)	Å	C85	H851	0.927	Å
C86	C87	1.360(16)	Å	C86	H861	0.936	Å
C87	C88	1.310(15)	Å	C87	H871	0.934	Å
C88	C89	1.386(14)	Å	C88	H881	0.935	Å
C89	H891	0.932	Å	S90	O91	1.459(5)	Å
S90	O92	1.454(6)	Å	S90	O93	1.431(5)	Å
S90	C94	1.793(8)	Å	C94	C95	1.383(11)	Å
C94	C99	1.354(11)	Å	C95	C96	1.356(13)	Å
C95	H951	0.938	Å	C96	C97	1.428(17)	Å
C96	H961	0.934	Å	C97	C98	1.323(15)	Å
C97	H971	0.924	Å	C98	C99	1.409(13)	Å
C98	H981	0.927	Å	C99	H991	0.924	Å
Br1	C2	1.886(6)	Å	C2	C3	1.382(9)	Å
C2	C7	1.381(9)	Å	C3	C4	1.358(10)	Å
C3	H31	0.928	Å	C4	C5	1.388(9)	Å
C4	H41	0.937	Å	C5	C6	1.398(9)	Å
C5	N18	1.454(8)	Å	C6	C7	1.394(9)	Å
C6	C8	1.498(9)	Å	C7	H71	0.926	Å
C8	C9	1.500(9)	Å	C8	N15	1.274(8)	Å
C9	N10	1.343(9)	Å	C9	C14	1.386(9)	Å
N10	C11	1.345(10)	Å	C11	C12	1.379(11)	Å
C11	H111	0.933	Å	C12	C13	1.375(11)	Å
C12	H121	0.927	Å	C13	C14	1.351(10)	Å
C13	H131	0.918	Å	C14	H141	0.921	Å
N15	C16	1.492(9)	Å	C16	C17	1.500(9)	Å
C16	C23	1.511(9)	Å	C16	H161	0.988	Å
C17	N18	1.352(8)	Å	C17	N21	1.315(8)	Å
N18	C19	1.400(8)	Å	C19	C20	1.344(9)	Å
C19	C22	1.496(9)	Å	C20	N21	1.376(8)	Å
C20	H201	0.927	Å	N21	H211	1.000	Å
C22	H221	0.958	Å	C22	H222	0.950	Å
C22	H223	0.953	Å	C23	C24	1.536(11)	Å
C23	H231	0.962	Å	C23	H232	0.969	Å
C24	C25	1.470(11)	Å	C24	H241	0.971	Å
C24	H242	0.962	Å	C25	O26	1.202(10)	Å
C25	O27	1.354(10)	Å	O27	C28	1.445(10)	Å
C28	H281	1.000	Å	C28	H282	1.000	Å
C28	H283	1.000	Å	Br51	C52	1.886(7)	Å
C52	C53	1.366(11)	Å	C52	C57	1.412(10)	Å
C53	C54	1.404(11)	Å	C53	H531	0.927	Å
C54	C55	1.383(10)	Å	C54	H541	0.921	Å
C55	C56	1.414(9)	Å	C55	N68	1.427(9)	Å
C56	C57	1.396(9)	Å	C56	C58	1.489(9)	Å
C57	H571	0.925	Å	C58	C59	1.530(10)	Å
C58	N65	1.254(8)	Å	C59	N60	1.314(9)	Å
C59	C64	1.391(10)	Å	N60	C61	1.372(10)	Å
C61	C62	1.386(14)	Å	C61	H611	0.918	Å
C62	C63	1.355(15)	Å	C62	H621	0.928	Å
C63	C64	1.378(13)	Å	C63	H631	0.932	Å
C64	H641	0.917	Å	N65	C66	1.485(8)	Å
C66	C67	1.474(9)	Å	C66	C73	1.516(10)	Å
C66	H661	0.982	Å	C67	N68	1.354(9)	Å
C67	N71	1.334(8)	Å	N68	C69	1.406(9)	Å
C69	C70	1.343(11)	Å	C69	C72	1.484(12)	Å
C70	N71	1.366(10)	Å	C70	H701	0.925	Å
N71	H711	1.000	Å	C72	H721	0.964	Å
C72	H722	0.958	Å	C72	H723	0.965	Å
C73	C74	1.535(10)	Å	C73	H731	0.975	Å
C73	H732	0.967	Å	C74	C75	1.493(12)	Å
C74	H741	0.972	Å	C74	H742	0.977	Å
C75	O76	1.185(9)	Å	C75	O77	1.360(9)	Å
O77	C78	1.440(11)	Å	C78	H781	0.965	Å
C78	H782	0.966	Å	C78	H783	0.960	Å

TABLE 20
Angles for Compound of formula (I) besylate Form 1
O81	S80	O82	111.0(3)°	O81	S80	O83	112.9(4)°
O82	S80	O83	114.4(4)°	O81	S80	C84	105.5(3)°
O82	S80	C84	106.2(3)°	O83	S80	C84	106.0(4)°
S80	C84	C85	117.7(6)°	S80	C84	C89	123.6(7)°
C85	C84	C89	118.3(8)°	C84	C85	C86	120.0(9)°
C84	C85	H851	119.626°	C86	C85	H851	120.377°
C85	C86	C87	118.1(10)°	C85	C86	H861	120.636°
C87	C86	H861	121.303°	C86	C87	C88	121.8(10)°
C86	C87	H871	119.251°	C88	C87	H871	118.984°
C87	C88	C89	119.3(10)°	C87	C88	H881	120.392°
C89	C88	H881	120.264°	C84	C89	C88	122.5(10)°
C84	C89	H891	118.485°	C88	C89	H891	119.061°
O91	S90	O92	111.7(3)°	O91	S90	O93	112.8(4)°
O92	S90	O93	113.5(3)°	O91	S90	C94	104.5(3)°
O92	S90	C94	105.7(3)°	O93	S90	C94	108.0(3)°
S90	C94	C95	120.6(6)°	S90	C94	C99	120.1(6)°
C95	C94	C99	119.3(8)°	C94	C95	C96	121.6(9)°
C94	C95	H951	118.566°	C96	C95	H951	119.820°
C95	C96	C97	118.4(10)°	C95	C96	H961	119.911°
C97	C96	H961	121.695°	C96	C97	C98	119.9(8)°
C96	C97	H971	119.699°	C98	C97	H971	120.397°
C97	C98	C99	120.8(9)°	C97	C98	H981	119.080°
C99	C98	H981	120.094°	C94	C99	C98	119.9(9)°
C94	C99	H991	119.276°	C98	C99	H991	120.819°
Br1	C2	C3	121.0(5)°	Br1	C2	C7	118.5(5)°
C3	C2	C7	120.5(5)°	C2	C3	C4	119.7(6)°
C2	C3	H31	120.203°	C4	C3	H31	120.109°
C3	C4	C5	120.6(6)°	C3	C4	H41	120.600°
C5	C4	H41	118.766°	C4	C5	C6	120.6(6)°
C4	C5	N18	119.6(5)°	C6	C5	N18	119.8(6)°
C5	C6	C7	117.8(6)°	C5	C6	C8	123.3(6)°
C7	C6	C8	118.8(6)°	C2	C7	C6	120.6(6)°
C2	C7	H71	119.721°	C6	C7	H71	119.679°
C6	C8	C9	117.5(5)°	C6	C8	N15	126.6(6)°
C9	C8	N15	115.9(6)°	C8	C9	N10	114.9(6)°
C8	C9	C14	121.2(6)°	N10	C9	C14	123.9(6)°
C9	N10	C11	115.5(6)°	N10	C11	C12	124.4(7)°
N10	C11	H111	118.526°	C12	C11	H111	117.061°
C11	C12	C13	117.4(7)°	C11	C12	H121	121.279°
C13	C12	H121	121.289°	C12	C13	C14	120.4(6)°
C12	C13	H131	119.499°	C14	C13	H131	120.125°
C9	C14	C13	118.3(6)°	C9	C14	H141	120.274°
C13	C14	H141	121.419°	C8	N15	C16	118.0(5)°
N15	C16	C17	105.9(5)°	N15	C16	C23	109.4(5)°
C17	C16	C23	112.4(5)°	N15	C16	H161	110.723°
C17	C16	H161	109.539°	C23	C16	H161	108.851°
C16	C17	N18	122.7(6)°	C16	C17	N21	130.3(6)°
N18	C17	N21	106.5(5)°	C5	N18	C17	123.1(5)°
C5	N18	C19	127.0(5)°	C17	N18	C19	109.8(5)°
N18	C19	C20	105.2(5)°	N18	C19	C22	125.3(6)°
C20	C19	C22	129.4(6)°	C19	C20	N21	108.0(5)°
C19	C20	H201	126.017°	N21	C20	H201	126.026°
C17	N21	C20	110.5(5)°	C17	N21	H211	124.840°
C20	N21	H211	124.681°	C19	C22	H221	109.508°
C19	C22	H222	109.778°	H221	C22	H222	108.808°
C19	C22	H223	110.905°	H221	C22	H223	108.786°
H222	C22	H223	109.018°	C16	C23	C24	112.3(6)°
C16	C23	H231	109.392°	C24	C23	H231	108.812°
C16	C23	H232	108.378°	C24	C23	H232	109.105°
H231	C23	H232	108.825°	C23	C24	C25	114.3(7)°
C23	C24	H241	109.968°	C25	C24	H241	110.030°
C23	C24	H242	108.195°	C25	C24	H242	105.346°
H241	C24	H242	108.752°	C24	C25	O26	126.4(7)°
C24	C25	O27	109.4(7)°	O26	C25	O27	123.9(7)°
C25	O27	C28	115.2(7)°	O27	C28	H281	109.674°
O27	C28	H282	109.261°	H281	C28	H282	109.475°
O27	C28	H283	109.465°	H281	C28	H283	109.476°
H282	C28	H283	109.476°	Br51	C52	C53	119.3(6)°
Br51	C52	C57	119.0(5)°	C53	C52	C57	121.7(7)°
C52	C53	C54	118.9(7)°	C52	C53	H531	120.141°
C54	C53	H531	120.985°	C53	C54	C55	119.8(7)°
C53	C54	H541	120.227°	C55	C54	H541	120.000°
C54	C55	C56	122.1(6)°	C54	C55	N68	119.4(6)°
C56	C55	N68	118.5(6)°	C55	C56	C57	117.2(6)°
C55	C56	C58	123.2(6)°	C57	C56	C58	119.5(6)°
C52	C57	C56	120.2(7)°	C52	C57	H571	119.709°
C56	C57	H571	120.138°	C56	C58	C59	116.5(6)°
C56	C58	N65	126.7(6)°	C59	C58	N65	116.8(6)°
C58	C59	N60	116.3(6)°	C58	C59	C64	118.5(7)°
N60	C59	C64	125.0(7)°	C59	N60	C61	116.1(7)°
N60	C61	C62	121.7(8)°	N60	C61	H611	119.342°
C62	C61	H611	118.993°	C61	C62	C63	120.6(8)°
C61	C62	H621	120.029°	C63	C62	H621	119.353°
C62	C63	C64	118.4(9)°	C62	C63	H631	120.452°
C64	C63	H631	121.124°	C59	C64	C63	118.1(8)°
C59	C64	H641	120.844°	C63	C64	H641	121.057°
C58	N65	C66	118.2(6)°	N65	C66	C67	105.4(5)°
N65	C66	C73	109.7(5)°	C67	C66	C73	111.5(6)°
N65	C66	H661	109.122°	C67	C66	H661	108.890°
C73	C66	H661	112.017°	C66	C67	N68	121.8(6)°
C66	C67	N71	130.3(7)°	N68	C67	N71	107.4(6)°
C55	N68	C67	122.5(6)°	C55	N68	C69	128.7(6)°
C67	N68	C69	108.7(6)°	N68	C69	C70	105.5(6)°
N68	C69	C72	124.0(7)°	C70	C69	C72	130.5(7)°
C69	C70	N71	109.1(6)°	C69	C70	H701	125.444°
N71	C70	H701	125.502°	C67	N71	C70	109.2(6)°
C67	N71	H711	125.400°	C70	N71	H711	125.366°
C69	C72	H721	110.667°	C69	C72	H722	109.838°
H721	C72	H722	108.539°	C69	C72	H723	110.831°
H721	C72	H723	108.455°	H722	C72	H723	108.445°
C66	C73	C74	111.0(6)°	C66	C73	H731	108.535°
C74	C73	H731	110.248°	C66	C73	H732	110.751°
C74	C73	H732	108.249°	H731	C73	H732	108.042°
C73	C74	C75	112.4(6)°	C73	C74	H741	108.496°
C75	C74	H741	109.125°	C73	C74	H742	108.155°
C75	C74	H742	108.578°	H741	C74	H742	110.035°
C74	C75	O76	126.2(7)°	C74	C75	O77	110.7(7)°
O76	C75	O77	123.0(7)°	C75	O77	C78	115.6(7)°
O77	C78	H781	109.214°	O77	C78	H782	109.848°
H781	C78	H782	109.923°	O77	C78	H783	109.687°
H781	C78	H783	109.026°	H782	C78	H783	109.127°

TABLE 21
Bond Lengths for Compound of formula (I) besylate Form 2.
Br1	C2	1.892(3)	Å	C2	C3	1.387(5)	Å
C2	C7	1.383(5)	Å	C3	C4	1.371(5)	Å
C3	H31	0.938	Å	C4	C5	1.392(5)	Å
C4	H41	0.921	Å	C5	C6	1.406(4)	Å
C5	N18	1.428(4)	Å	C6	C7	1.395(5)	Å
C6	C8	1.497(4)	Å	C7	H71	0.924	Å
C8	C9	1.497(4)	Å	C8	N15	1.276(4)	Å
C9	N10	1.338(4)	Å	C9	C14	1.395(5)	Å
N10	C11	1.345(4)	Å	C11	C12	1.378(5)	Å
C11	H111	0.935	Å	C12	C13	1.370(5)	Å
C12	H121	0.948	Å	C13	C14	1.382(5)	Å
C13	H131	0.936	Å	C14	H141	0.934	Å
N15	C16	1.478(4)	Å	C16	C17	1.487(5)	Å
C16	C23	1.527(5)	Å	C16	H161	0.976	Å
C17	N18	1.346(4)	Å	C17	N21	1.320(4)	Å
N18	C19	1.391(4)	Å	C19	C20	1.342(5)	Å
C19	C22	1.494(5)	Å	C20	N21	1.378(5)	Å
C20	H201	0.912	Å	N21	H211	0.854	Å
C22	H221	0.965	Å	C22	H222	0.966	Å
C22	H223	0.960	Å	C23	C24	1.534(5)	Å
C23	H231	0.969	Å	C23	H232	0.981	Å
C24	C25	0.478(5)	Å	C24	H241	0.960	Å
C24	H242	0.988	Å	C25	O26	1.201(4)	Å
C25	O27	1.342(4)	Å	C27	C28	1.451(5)	Å
C28	H281	0.964	Å	C28	H282	0.965	Å
C28	H283	0.962	Å	S80	O81	1.431(3)	Å
S80	O82	1.447(3)	Å	S80	O83	1.430(3)	Å
S80	C84	1.774(4)	Å	C84	C85	1.400(7)	Å
C84	C89	1.369(7)	Å	C85	C86	1.380(7)	Å
C85	H851	0.932	Å	C86	C87	1.342(13)	Å
C86	H861	0.943	Å	C87	C88	1.410(13)	Å
C87	H871	0.934	Å	C88	C89	1.433(10)	Å
C88	H881	0.925	Å	C89	H891	0.940	Å

TABLE 22
Angles for Compound of formula (I) besylate Form 2.
Br1	C2	C3	119.3(3)°	Br1	C2	C7	118.9(3)°
C3	C2	C7	121.8(3)°	C2	C3	C4	119.0(3)°
C2	C3	H31	120.033°	C4	C3	H31	120.959°
C3	C4	C5	120.3(3)°	C3	C4	H41	119.485°
C5	C4	H41	120.261°	C4	C5	C6	121.0(3)°
C4	C5	N18	118.9(3)°	C6	C5	N18	120.1(3)°
C5	C6	C7	118.2(3)°	C5	C6	C8	122.3(3)°
C7	C6	C8	119.5(3)°	C2	C7	C6	119.7(3)°
C2	C7	H71	120.432°	C6	C7	H71	119.874°
C6	C8	C9	117.7(3)°	C6	C8	N15	124.4(3)°
C9	C8	N15	117.9(3)°	C8	C9	N10	116.6(3)°
C8	C9	C14	120.0(3)°	N10	C9	C14	123.4(3)°
C9	N10	C11	116.7(3)°	N10	C11	C12	123.7(3)°
N10	C11	H111	117.041°	C12	C11	H111	119.278°
C11	C12	C13	118.8(3)°	C11	C12	H121	120.443°
C13	C12	H121	120.783°	C12	C13	C14	119.3(3)°
C12	C13	H131	120.694°	C14	C13	H131	119.952°
C9	C14	C13	118.1(3)°	C9	C14	H141	120.942°
C13	C14	H141	120.983°	C8	N15	C16	117.6(3)°
N15	C16	C17	105.7(3)°	N15	C16	C23	110.8(3)°
C17	C16	C23	115.7(3)°	N15	C16	H161	107.681°
C17	C16	H161	107.726°	C23	C16	H161	108.910°
C16	C17	N18	120.7(3)°	C16	C17	N21	131.2(3)°
N18	C17	N21	108.0(3)°	C5	N18	C17	122.3(3)°
C5	N18	C19	128.6(3)°	C17	N18	C19	109.0(3)°
N18	C19	C20	105.7(3)°	N18	C19	C22	124.9(3)°
C20	C19	C22	129.3(3)°	C19	C20	N21	108.6(3)°
C19	C20	H201	127.007°	N21	C20	H201	124.433°
C17	N21	C20	108.7(3)°	C17	N21	H211	125.926°
C20	N21	H211	125.351°	C19	C22	H221	110.223°
C19	C22	H222	109.368°	H221	C22	H222	108.664°
C19	C22	H223	111.184°	H221	C22	H223	109.452°
H222	C22	H223	107.885°	C16	C23	C24	107.9(3)°
C16	C23	H231	107.712°	C24	C23	H231	110.073°
C16	C23	H232	111.123°	C24	C23	H232	109.430°
H231	C23	H232	110.583°	C23	C24	C25	118.8(3)°
C23	C24	H241	107.661°	C25	C24	H241	104.516°
C23	C24	H242	109.365°	C25	C24	H242	106.503°
H241	C24	H242	109.671°	C24	C25	O26	123.3(3)°
C24	C25	O27	114.4(3)°	O26	C25	O27	122.4(3)°
C25	O27	C28	115.2(3)°	O27	C28	H281	108.952°
O27	C28	H282	110.269°	H281	C28	H282	109.738°
O27	C28	H283	108.681°	H281	C28	H283	110.225°
H282	C28	H283	108.963°	O81	S80	O82	111.9(2)°
O81	S80	O83	115.1(2)°	O82	S80	O83	111.2(3)°
O81	S80	C84	106.30(18)°	O82	S80	C84	104.5(2)°
O83	S80	C84	107.0(2)°	S80	C84	C85	117.6(4)°
S80	C84	C89	122.1(4)°	C85	C84	C89	120.2(5)°
C84	C85	C86	121.6(6)°	C84	C85	H851	119.148°
C86	C85	H851	119.275°	C85	C86	C87	117.5(8)°
C85	C86	H861	121.859°	C87	C86	H861	120.606°
C86	C87	C88	124.9(7)°	C86	C87	H871	117.763°
C88	C87	H871	117.376°	C87	C88	C89	116.0(7)°
C87	C88	H881	122.592°	C89	C88	H881	121.435°
C84	C89	C88	119.8(8)°	C84	C89	H891	120.080°
C88	C89	H891	120.078°

Claims

1. A besylate salt of a compound of formula (I):

2. The salt according to claim 1, which is a crystalline salt.

3. The besylate salt according to claim 2 which is a crystalline polymorph that exhibits an X-ray powder diffraction (XRPD) pattern which comprises characteristic peaks at about 7.3, 7.8, 9.4, 12.1, 14.1, 14.4, 14.7, and 15.6 degrees two-theta.

4. The besylate salt according to claim 2 which is a crystalline polymorph comprising a crystal with unit cell dimensions of a=7.6868 Å, b=29.2607 Å, c=12.3756 Å, α=90°, β=97.7880°, γ=90°.

5. The besylate salt according to claim 2, which is a crystalline polymorph having a crystal structure defined by the structural coordinates as shown in Table 17.

6. The besylate salt according to claim 2, which is a crystalline polymorph having a crystal structure with bond lengths and angles as shown in Tables 19 and 20.

7. The besylate salt according to claim 2 which is a crystalline polymorph that exhibits an XRPD pattern which comprises characteristic peaks at about 8.6, 10.5, 12.0, 13.1, 14.4, and 15.9 degrees two-theta.

8. The besylate salt according to claim 2 which is a crystalline polymorph comprising a crystal with unit cell dimensions of a=8.92130 Å, b=11.1536 Å, c=25.8345 Å, α=90°, β=90°, γ=90°.

9. The besylate salt according to claim 2 which is a crystalline polymorph having a crystal structure defined by the structural coordinates as shown in Table 18.

10. The besylate salt according to claim 2 which is a crystalline polymorph having a crystal structure with bond lengths and angles as shown in Tables 21 and 22.

11. The besylate salt according to claim 2 which is a crystalline polymorph of a besylate salt of a compound of formula (I), that exhibits an X-ray powder diffraction pattern which comprises characteristic peaks at about 7.6, 11.2, 12.4, 14.6, 15.2, 16.4, and 17.7 degrees two-theta.

12. The besylate salt according to claim 2 which is a crystalline polymorph of a besylate salt of a compound of formula (I) that exhibits an XRPD pattern which comprises characteristic peaks at about 7.6, 10.8, 15.2, 15.9 and 22.0 degrees two-theta.

13. The pharmaceutical composition comprising a salt according to claim 1, and a pharmaceutically acceptable carrier, excipient, or diluent.

14. A salt according to claim 1 for use as a medicament.

15. Use of a sedative or hypnotic amount of a salt according to claim 1 in the manufacture of a medicament for producing sedation or hypnosis in a subject.

16. Use of an anxiolytic amount of a salt according to claim 1 in the manufacture of a medicament for producing anxiolysis in a subject.

17. Use of a muscle relaxant amount of a salt according to claim 1 in the manufacture of a medicament for producing muscle relaxation in a subject.

18. Use of an anticonvulsant amount of a salt according to claim 1 in the manufacture of a medicament for treating convulsions in a subject.

19. A method of making a salt according to claim 1, which comprises reacting a free base of a compound of formula (I) with benzene sulphonic acid.

20. The method according to claim 19, which comprises contacting the free base with benzene sulphonic acid in solution to cause formation of a precipitate of the besylate salt.

21. The method according to claim 20, which further comprises isolating the precipitate.

22. The method according to claim 20, wherein the free base is dissolved in toluene or ethyl acetate.

23. The method according to claim 20, wherein the benzene sulphonic acid is dissolved in ethanol.

24. The method according to claim 20 of preparing a salt according to formula (1) which is a crystalline polymorph that exhibits an X-ray powder diffraction pattern which comprises characteristic peaks at about 7.3, 7.8, 9.4, 12.1, 14.1, 14.4, 14.7, and 15.6 degrees two-theta, which comprises contacting a solution of a free base of the compound of formula (I) in toluene, ethyl acetate, acetone, isopropyl acetate, or ethyl formate with a solution of benzene sulphonic acid in ethanol to cause formation of a precipitate of the salt.

25. The method according to claim 20 of preparing a salt according to formula (I) which is a crystalline polymorph that exhibits an XRPD pattern which comprises characteristic peaks at about 8.6, 10.5, 12.0, 13.1, 14.4, and 15.9 degrees two-theta, which comprises contacting a solution of a free base of a the compound of formula (I) in methanol with a solution of benzene sulphonic acid in ethanol to cause formation of a precipitate of the salt.

26. The method of preparing a salt according to claim 11, which comprises seeding, with a besylate Form 1 crystalline salt of a compound of formula (I), a filtrate solution separated from the precipitate formed by contacting a solution of a compound of formula (I) in ethyl acetate with a solution of benzene sulphonic acid in ethanol, to produce the crystalline polymorph.

27. The method of preparing a salt according to claim 12, which comprises re-crystallising a besylate Form 1 crystalline salt of a compound of formula (I) from isopropyl acetate/ethanol.

28. The method of preparing a salt according to claim 2, which comprises crystallising a compound of formula (I) besylate from a solvent, or from a solvent/anti-solvent or solvent/co-solvent mixture.

29. A method for producing sedation or hypnosis in a subject, which comprises administering an effective sedative or hypnotic amount of a salt according to claim 1 to the subject.

30. A method for inducing anxiolysis in a subject, which comprises administering an effective anxiolytic amount of a salt according to claim 1 to the subject.

31. A method for inducing muscle relaxation in a subject, which comprises administering an effective muscle relaxant amount of a salt according to claim 1 to the subject.

32. A method for treating convulsions in a subject, which comprises administering an effective anticonvulsant amount of a salt according to claim 1 to the subject.